Drug-induced nutrient depletion

Medications That May Deplete L-CARNITINE

Carnitine shuttles fatty acids into cells' mitochondria so they can be burned for energy. See which medications carry a reported association, how strong the evidence is, and what to discuss with your pharmacist.

49Medications
49Depletion records
About L-CARNITINE

Carnitine shuttles fatty acids into cells' mitochondria so they can be burned for energy.

Common food sources: Red meat (the richest source); Poultry and fish; Dairy products.

Carnitine questions come up with specific medications (for example, valproic acid) and specific situations — this is a conversation for your prescriber, who can weigh testing or supplementation.

HelloPharmacist pharmacist-reviewed education. The medication records below are licensed clinical data, shown as published.

Deep dive: L-carnitine — uses, safety & drug interactions

The evidence

Medications associated with L-CARNITINE depletion

Each record is shown as published in our licensed clinical database. Open a medication for its full nutrient report.

Adefovir

Insignificant Depletion

Brand names include Hepsera

L-carnitine levels may be reduced in patients taking adefovir dipivoxil.

Adefovir dipivoxil is converted to adefovir and pivalate in the body; pivalate combines with carnitine and is excreted in the urine, increasing L-carnitine losses. Adefovir was formerly used at doses of 125-500 mg daily, and was associated with significant dose- and duration-related decreases in blood carnitine. After 12 weeks of therapy with 125-250 mg daily, decreases of 42% to 62% were seen; while 500 mg daily was associated with a 66% decrease in L-carnitine after 2 weeks. Some studies used a supplement of L-carnitine 500 mg daily during adefovir therapy. Adefovir is now used at a lower dose of 10 mg daily for treatment of hepatitis B. There are no reports of significant reductions in carnitine blood levels at this dose, and supplements are not necessary.
Taking Adefovir? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to help turn fat into energy, and your muscles depend on it to work properly. When adefovir is broken down in the body, one of its byproducts latches onto carnitine and carries it out through the urine, which can gradually reduce your levels. That said, adefovir is now prescribed at a much lower dose (10 mg daily) than in older studies, and at this dose there are no reports of meaningful carnitine loss. For most people taking adefovir today, this is not something that requires action, but feel free to mention it to your pharmacist if you have any concerns.

References (5)
  1. Brass EP. Pivalate-generating prodrugs and carnitine homeostasis in man. Pharmacol Rev 2002;54:589-98. PubMed
  2. Deeks SG, Collier A, Lalezari J, et al. The safety and efficacy of adefovir dipivoxil, a novel anti-human immunodeficiency virus (HIV) therapy, in HIV-infected adults: a randomized, double-blind, placebo-controlled trial. J Infect Dis 1997;176:1517-23. PubMed
  3. Barditch-Crovo P, Toole J, Hendrix CW, et al. Anti-human immunodeficiency virus (HIV) activitiy, safety, and pharmacokinetics of adefovir dipivoxyl (9-[2-(bis-pivaloyloxymethyl)-phosphonylmethoxyethyl]adenine) in HIV-infected patients. J Infect Dis 1997;1
  4. Kahn J, Lagakos S, Wulfsohn M, et al. Efficacy and safety of adefovir dipivoxil with antiretroviral therapy. J Am Med Assoc 1999;282:2305-12.
  5. Noble S, Goa KL. Adefovir dipivoxil. Drugs 1999;58:479-87.

Full nutrient report for Adefovir →

Brand names include Triple Barbital

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Aprobarbital, Butabarbital, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, and some research has found lower levels of it in people taking phenobarbital. The exact reason is not fully clear, and other studies have seen no meaningful change at all. Given that this is considered an insignificant depletion, routine supplementation is not something most people on these medications need to worry about. Still, if you have questions or any unusual fatigue, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Aprobarbital, Butabarbital, Phenobarbital →

Brand names include Phenaphen

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Aspirin, Codeine Phosphate, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital is the ingredient in this combination that researchers have looked at in connection with L-carnitine, a compound your body uses to turn fat into usable energy for muscles and cells. Some studies have found slightly lower L-carnitine levels in people taking phenobarbital long-term, though other studies showed no meaningful change at all. Because the evidence is mixed and the overall rating here is insignificant, most people taking this medication do not need to worry about or act on this. If you have been on phenobarbital for a long time and are curious, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Aspirin, Codeine Phosphate, Phenobarbital →

Atropine, Hyoscyamine, Phenobarbital

Insignificant Depletion

Brand names include Hypnaldyne

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Atropine, Hyoscyamine, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital, one of the ingredients in this combination, has shown up in some research as possibly affecting L-carnitine levels, a nutrient your muscles and cells use to turn fat into energy. The evidence is genuinely mixed though: some studies found lower levels in people taking phenobarbital, while others found no real difference. Given that this is rated as an insignificant depletion, most people taking this medication do not need to worry about it or add a supplement. If you have questions or take phenobarbital long-term, it is always fine to bring it up with your pharmacist.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Atropine, Hyoscyamine, Phenobarbital →

Brand names include Barbidonna No. 2, Belladonna Phenobarbital

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Atropine, Hyoscyamine, Phenobarbital, Scopolamine? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital, one of the ingredients in this combination, has been studied in connection with L-carnitine, a substance your body uses to turn fat into usable energy, especially for muscles and the heart. A few studies found lower L-carnitine levels in some people taking phenobarbital, though other studies saw no meaningful change at all. Because the research is mixed and the overall rating here is insignificant, most people taking this medication are unlikely to need any action. If you take this combination long-term and have concerns, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Atropine, Hyoscyamine, Phenobarbital, Scopolamine →

Brand names include Barbeloid, Donnatal #2, Donphen

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Atropine, Hyoscyamine, Scopolamine, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to convert fat into energy, and some research has found lower levels of it in certain patients taking phenobarbital over time. The thinking is that phenobarbital may speed up liver enzymes that break down or interfere with carnitine metabolism, though studies have been mixed and no clear effect has been proven. Because the evidence is inconsistent and the rating here is insignificant, most people on this combination do not need to worry about supplementing. If you have been on phenobarbital long-term and have questions, it is worth a quick chat with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Atropine, Hyoscyamine, Scopolamine, Phenobarbital →

Atropine, Phenobarbital

Insignificant Depletion

Brand names include Anthrocol

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Atropine, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital is the piece of this combination that researchers have looked at in relation to L-carnitine, a compound your body uses to turn fat into usable energy. Some studies have found that people taking phenobarbital long-term show lower carnitine levels, possibly because the drug speeds up certain liver enzymes that affect how the body handles it, though other studies found no meaningful change at all. Given that the overall evidence is rated insignificant, routine supplementation is not considered necessary for most people. If you have been on phenobarbital for a long time and have questions, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Atropine, Phenobarbital →

Belladona Extract, Phenobarbital

Insignificant Depletion

Brand names include Chardonna-2

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Belladona Extract, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to convert fat into energy, and some research has found lower levels of it in people taking phenobarbital, possibly because the drug may interfere with how the body produces or retains it. That said, other studies found no meaningful difference, and the overall evidence is considered insignificant, meaning most people on this medication do not need to worry about it or take a supplement. If you have concerns, a quick conversation with your pharmacist or doctor can put your mind at ease.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Belladona Extract, Phenobarbital →

Brand names include Bellaphen-S, Spastrin, Phenarbal S

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Belladonna Alkaloids, Ergotamine Tartrate, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital, one of the ingredients in this combination, has shown up in some research as potentially affecting L-carnitine, a compound your body uses to turn fat into usable energy. The evidence is mixed, though: some studies found lower levels in people taking phenobarbital, while others found no real difference at all. Given that this is rated as an insignificant depletion, most people taking this medication do not need to worry about it or add a supplement. If you have any concerns, your pharmacist or doctor is the right person to ask.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Belladonna Alkaloids, Ergotamine Tartrate, Phenobarbital →

Belladonna Alkaloids, Phenobarbital

Insignificant Depletion

Brand names include Barbidonna, Donnatal

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Belladonna Alkaloids, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into energy, and it plays a supporting role in muscle and heart function. The phenobarbital component of this medication has shown up in some research as potentially lowering L-carnitine levels, possibly because it affects how the body processes and clears certain nutrients over time. That said, the evidence is mixed, with other studies finding no meaningful change, and the overall rating here is insignificant. Most people on this medication do not need to take an L-carnitine supplement, but if you have been on phenobarbital long-term and have questions, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Belladonna Alkaloids, Phenobarbital →

Belladonna Extract, Phenobarbital

Insignificant Depletion

Brand names include Belap

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Belladonna Extract, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, particularly in muscle cells. Phenobarbital, the anticonvulsant in this combination, has been reported in some studies to reduce L-carnitine levels, possibly because it affects how the body processes and clears certain nutrients over time. That said, other studies found no meaningful change, and the overall evidence is rated as insignificant, meaning most people taking this medication do not need to worry about it or take a supplement. If you have been on phenobarbital for a long time and have concerns, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Belladonna Extract, Phenobarbital →

Belladonna, Ergotamine, Phenobarbital

Insignificant Depletion

Brand names include Bellergal-S

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Belladonna, Ergotamine, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, and phenobarbital (one of the ingredients in this combination) has shown up in some studies as potentially lowering L-carnitine levels, possibly by affecting how the body processes or holds onto it. That said, other studies found no real difference, and overall the evidence is considered insignificant. For most people taking this medication, routine supplementation is not thought to be necessary. If you have any concerns, it is always worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Belladonna, Ergotamine, Phenobarbital →

Belladonna, Phenobarbital

Insignificant Depletion

Brand names include Bellophen, Susano

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Belladonna, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, and some research has found that phenobarbital may reduce its levels in certain patients, possibly because the drug affects how the body processes or retains it. That said, other studies found no meaningful change, and the overall evidence here is rated as insignificant. For most people taking this medication, there is no need to worry or do anything differently. If you have concerns, a quick conversation with your pharmacist or doctor can put your mind at ease.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Belladonna, Phenobarbital →

Bellafoline, Phenobarbital

Insignificant Depletion

Brand names include Belladenal, Belladenal-S

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Bellafoline, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into fuel, especially for muscles and the heart. Some research has found lower L-carnitine levels in people taking phenobarbital, possibly because the drug speeds up how the liver processes certain compounds, which may increase how quickly carnitine is used or cleared. That said, other studies have not found a meaningful difference, and the overall evidence is rated insignificant, meaning routine supplementation is not considered necessary for most people. If you have concerns, it is always fine to bring them up with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Bellafoline, Phenobarbital →

Brand names include S.B.P.

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Butabarbital, Phenobarbital, Secobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, and some research has looked at whether phenobarbital might nudge levels lower, possibly by affecting how the body processes or holds onto it. The picture is mixed, though: some studies spotted a reduction in certain patients, while others found no meaningful change at all. Given that this is rated an insignificant depletion, routine supplementation is not considered necessary for most people on these medications. If you have any lingering questions, your pharmacist or doctor can help you sort out whether your individual situation warrants a closer look.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Butabarbital, Phenobarbital, Secobarbital →

Butalbital, Phenobarbital, Secobarbital

Insignificant Depletion

Brand names include Tribarb

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Butalbital, Phenobarbital, Secobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, particularly in muscle cells. Some research has found that phenobarbital may lower L-carnitine levels in certain patients, possibly because it affects how the body processes and transports this compound, though the exact reason is not fully understood. Importantly, other studies found no meaningful change at all, which is why this is rated as an insignificant depletion. Most people taking these barbiturate medications do not need to take L-carnitine supplements, but if you have concerns, your pharmacist or doctor is the right person to ask.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Butalbital, Phenobarbital, Secobarbital →

Brand names include Nevrotose #3

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Camphor, Hyoscyamine, Passif, Phenobarbital, Scopolamine, Valerian? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital is the ingredient in this combination product that research has looked at in connection with L-carnitine, a nutrient your muscles and heart use to turn fat into energy. A handful of studies have found lower L-carnitine levels in some people taking phenobarbital, possibly because the drug speeds up certain liver pathways that can affect how the body handles carnitine, though other studies found no real difference. The evidence is mixed and the overall rating here is insignificant, meaning routine supplementation is not considered necessary for most people. If you are a long-term phenobarbital user and have concerns, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Camphor, Hyoscyamine, Passif, Phenobarbital, Scopolamine, Valerian →

Carbamazepine

Insignificant Depletion

Brand names include Tegretol, Tegretol XR, Equetro

Theoretically, L-carnitine levels may be reduced in patients taking carbamazepine.

Data on the effect of carbamazepine on L-carnitine blood levels are conflicting. Some studies have found reduced levels in some patients on the drug, while others have found no effect. Routine L-carnitine supplementation is not necessary. Preliminary data in patients treated with the related drug oxcarbazepine (Trileptal) suggest that it does not affect L-carnitine levels.
Taking Carbamazepine? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Carnitine is a compound your muscles and heart use to convert fat into usable energy. Research on whether carbamazepine actually lowers carnitine levels is genuinely mixed, with some studies finding modest reductions and others finding no change at all. Given the conflicting data and an insignificant rating, most people taking carbamazepine do not need to worry about this or consider a supplement. If you have concerns, it is worth a quick conversation with your pharmacist or doctor.

References (6)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. De Vivo DC, Bohan TP, Coulter DL, et al. L-carnitine supplementation in childhood epilepsy: Current perspectives. Epilepsia 1998;39:1216-25.
  3. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed
  6. Kurul S, Dirik E, Iscan A. Serum carnitine levels during oxcarbazepine and carbamazepine monotherapies in children with epilepsy. J Child Neurol 2003;18:552-4. PubMed

Full nutrient report for Carbamazepine →

Cisplatin

Insignificant Depletion

Brand names include Platinol-AQ

L-carnitine levels may be reduced in patients taking cisplatin.

Increased urinary losses of L-carnitine can occur during cisplatin therapy. Cisplatin might increase L-carnitine mobilization due to tissue injury, and reduced renal tubular reabsorption due to renal injury. L-carnitine deficiency is unlikely in people who can maintain adequate dietary intake.
Taking Cisplatin? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into energy, and cisplatin has been reported to raise the amount lost through urine, likely because the drug can injure the kidneys and reduce how well they recapture carnitine before it gets flushed out. That said, the evidence rates this as insignificant, meaning most patients eating a reasonably normal diet are unlikely to develop a true deficiency. This is not something that typically calls for action, but if you are on long-term cisplatin therapy or have concerns about your diet, it is worth mentioning to your doctor or pharmacist.

References (1)
  1. Heuberger W, Berardi S, Jacky E, et al. Increased urinary excretion of carnitine in patients treated with cisplatin. Eur J Clin Pharmacol 1998;54:503-8. PubMed

Full nutrient report for Cisplatin →

Brand names include G.B.S.

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Dehydrocholic Acid, Homatropine Methylbromide, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital, one of the ingredients in this combination, has shown up in some research as possibly lowering L-carnitine, a compound your body uses to turn fat into usable energy. The exact reason is not fully understood, and other studies found no meaningful change at all. Given that the evidence is mixed and the overall rating is insignificant, most people taking this medication do not need to worry about L-carnitine supplementation, but if you have been on phenobarbital long term, it is worth mentioning to your pharmacist or doctor at your next visit.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Dehydrocholic Acid, Homatropine Methylbromide, Phenobarbital →

Dicyclomine, Phenobarbital

Insignificant Depletion

Brand names include Bentyl w/ Pb

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Dicyclomine, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital is the part of this combination that researchers have looked at in relation to L-carnitine, a compound your body uses to turn fat into usable energy. A few studies have found somewhat lower L-carnitine levels in people taking phenobarbital, possibly because the drug affects how the body processes and holds onto it, though other studies found no meaningful difference at all. The evidence here is rated insignificant, meaning most people on this medication do not need to worry about or supplement L-carnitine. If you have been on phenobarbital long-term and have questions, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Dicyclomine, Phenobarbital →

Brand names include Lufyllin-EPG

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Dyphylline, Ephedrine, Guaifenesin, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital is the ingredient in this combination that has been linked to lower L-carnitine levels, a compound your muscles and heart use to turn fat into usable energy. Researchers think phenobarbital may interfere with how the body handles carnitine, though the studies are genuinely mixed, with some showing reduced levels and others finding no meaningful change at all. Because the evidence is inconsistent and routine supplementation does not appear to be necessary for most people, this is rated insignificant. If you take phenobarbital long-term and have questions, your pharmacist or doctor can help you decide whether any monitoring makes sense for you.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Dyphylline, Ephedrine, Guaifenesin, Phenobarbital →

Brand names include Mudrane GG

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Ephedrine, Guaifenesin, Phenobarbital, Theophylline? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into energy, particularly for muscles and the heart. Some research has found that phenobarbital, one of the medications in this combination, may be linked to lower L-carnitine levels in certain patients, though other studies have not seen any meaningful difference. Because the evidence is mixed and the rating is insignificant, most people taking this medication do not need to worry about supplementing L-carnitine. If you have been on phenobarbital long-term and have concerns, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Ephedrine, Guaifenesin, Phenobarbital, Theophylline →

Brand names include Quadrinal, Mudrane

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Ephedrine, Phenobarbital, Potassium Iodide, Theophylline? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital is the medication in this combination that has been studied in relation to L-carnitine, a nutrient your muscles and heart use to turn fat into energy. A few studies have found slightly lower L-carnitine levels in some people taking phenobarbital, possibly because the drug speeds up how the liver processes certain compounds, but other studies found no meaningful difference at all. Given that the evidence is mixed and the overall rating is insignificant, most people on this medication do not need to worry about this or take a supplement. If you have been on phenobarbital long-term and have concerns, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Ephedrine, Phenobarbital, Potassium Iodide, Theophylline →

Ephedrine, Phenobarbital, Theophylline

Insignificant Depletion

Brand names include Tedral

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Ephedrine, Phenobarbital, Theophylline? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital is the focus here, and here is what some research has turned up: a handful of studies found lower levels of L-carnitine, a compound your body uses to turn fat into usable energy, in patients taking it long term. The honest picture is mixed, though, because other studies found no real difference at all. With an insignificant depletion rating, routine supplementation does not appear necessary for most people, but if you have been on phenobarbital for a long time and have questions, your pharmacist or doctor is a good first stop.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Ephedrine, Phenobarbital, Theophylline →

Ergotamine, Belladonna, Phenobarbital

Insignificant Depletion

Brand names include Bellaspas, Bellamine, Eperbel-S

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Ergotamine, Belladonna, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to convert fat into energy, and phenobarbital (one of the ingredients in this combination product) has shown up in some studies as possibly lowering L-carnitine levels, though researchers think it may affect how the body processes or uses carnitine rather than simply blocking it from being absorbed. The catch is that other studies found no real difference at all. Given the insignificant rating here, routine supplementation is not considered necessary for most people taking this medication. Still, if you have been on phenobarbital long-term and have questions, your pharmacist or doctor is the right person to ask.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Ergotamine, Belladonna, Phenobarbital →

Hyoscyamine, Phenobarbital

Insignificant Depletion

Brand names include Levsin Pb, Levsinex Pb Timecaps

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Hyoscyamine, Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Phenobarbital, one of the ingredients in this combination, has shown up in some research as potentially interfering with how the body handles L-carnitine, a compound your muscles and cells use to turn fat into usable energy. The picture from studies is mixed though: some found lower carnitine levels in people taking phenobarbital, while others found no real difference at all. Given that this is rated as insignificant, most people on this medication do not need to worry about it or take a supplement, but if you have been on it long-term and have any concerns, a quick conversation with your pharmacist or doctor can give you peace of mind.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Hyoscyamine, Phenobarbital →

Isotretinoin

Insignificant Depletion

Brand names include Accutane, Amnesteem, Claravis

Theoretically, L-carnitine levels may be reduced in patients taking isotretinoin.

Reduced carnitine blood levels have been reported with the use of isotretinoin, sometimes with symptoms of carnitine deficiency, such as myalgia and muscle stiffness. However, other studies have found no significant effect of isotretinoin on carnitine blood levels. There is not enough information to recommend routine use of L-carnitine supplements with isotretinoin.
Taking Isotretinoin? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into energy, and a few studies have noted lower carnitine blood levels in people taking isotretinoin, occasionally alongside muscle aches or stiffness. The leading theory is that isotretinoin may interfere with how the body produces or handles carnitine, though other studies found no meaningful change at all. Because the evidence is mixed and the rating is insignificant, most people on isotretinoin do not need to worry about this or take a supplement. If you have ongoing muscle discomfort while on isotretinoin, it is worth mentioning to your pharmacist or doctor.

References (2)
  1. Georgala S, Schulpis KH, Georgala C, Michas T. L-carnitine supplementation in patients with cystic acne on isotretinoin therapy. J Eur Acad Dermatol Venereol 1999;13:205-9. DOI
  2. Laker MF, Green C, Bhuiyan AK, Shuster S. Isotretinoin and serum lipids: studies on fatty acid, apolipoprotein and intermediary metabolism. Br J Dermatol 1987;117:203-6. PubMed

Full nutrient report for Isotretinoin →

Mephenytoin

Insignificant Depletion

Brand names include Mesantoin

Theoretically, L-carnitine levels may be reduced in patients taking phenytoin.

Some studies have found reduced L-carnitine levels in some patients on phenytoin, while others have found no effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Mephenytoin? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, and your muscles and heart depend on a steady supply of it. Mephenytoin is closely related to phenytoin, and some research has found that phenytoin-type medications may be linked to lower carnitine levels in certain patients, though other studies have seen no change at all. Given that the evidence is mixed and this is rated as an insignificant depletion, most people taking this medication do not need to worry about it or take a carnitine supplement. If you have concerns, it is always fine to bring them up with your pharmacist or doctor.

References (3)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. De Vivo DC, Bohan TP, Coulter DL, et al. L-carnitine supplementation in childhood epilepsy: Current perspectives. Epilepsia 1998;39:1216-25.
  3. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Mephenytoin →

Phenobarbital

Insignificant Depletion

Brand names include Solfoton, Luminal

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Phenobarbital? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, particularly in muscle cells. A few studies have spotted lower L-carnitine levels in some people on phenobarbital, possibly because the drug speeds up certain liver enzymes that affect how carnitine is processed and cleared. That said, other studies found no meaningful difference, and the overall evidence rates this as insignificant for most patients. Routine supplementation is not generally recommended, but if you have been on phenobarbital for a long time and have concerns, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Phenobarbital →

Phenobarbital, Phenytoin

Insignificant Depletion

Brand names include Dilantin with PB

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Phenobarbital, Phenytoin? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to convert fat into energy, and it plays a supporting role in muscle and nerve function. Some research has found lower carnitine levels in people taking phenobarbital, possibly because the drug speeds up certain liver enzymes that affect how carnitine is processed, but other studies have seen no real difference at all. Given the mixed evidence and an insignificant depletion rating, most people on phenobarbital do not need to worry about this or take a supplement. If you have been on this medication long-term and have questions, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Phenobarbital, Phenytoin →

Phenobarbital, Sodium Nitrate

Insignificant Depletion

Brand names include Soniphen

Theoretically, L-carnitine levels may be reduced in patients taking phenobarbital.

Some studies have found reduced levels of L-carnitine in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Phenobarbital, Sodium Nitrate? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into fuel for your cells, especially in muscles. Some research has found that phenobarbital may be linked to lower L-carnitine levels in certain patients, though other studies saw no meaningful change at all. Given that the evidence is mixed and the rating is insignificant, most people on phenobarbital do not need to take an L-carnitine supplement. If you have been on this medication long-term and are curious, it is worth a quick conversation with your pharmacist or doctor.

References (5)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  3. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Phenobarbital, Sodium Nitrate →

Phenytoin

Insignificant Depletion

Brand names include Dilantin Kapseals, Dilantin, Di-Phen

Theoretically, L-carnitine levels may be reduced in patients taking phenytoin.

Some studies have found reduced L-carnitine levels in some patients on phenytoin, while others have found no effect. Routine L-carnitine supplementation does not seem to be necessary.
Taking Phenytoin? A supplement is not needed for most patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, especially for muscles and the heart. Some research has noticed lower L-carnitine levels in people taking phenytoin, possibly because the drug interferes with how the body produces or recycles it, though other studies have seen no difference at all. Given that this is rated insignificant, most people on phenytoin do not need to worry about this or take a supplement. If you have concerns, your pharmacist or doctor can help you decide whether any monitoring makes sense for you.

References (3)
  1. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  2. De Vivo DC, Bohan TP, Coulter DL, et al. L-carnitine supplementation in childhood epilepsy: Current perspectives. Epilepsia 1998;39:1216-25.
  3. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed

Full nutrient report for Phenytoin →

Cefditoren Pivoxil

Moderate Depletion

Brand names include Spectracef

L-carnitine levels may be reduced in patients taking cefditoren pivoxil.

Cefditoren pivoxil is a prodrug which is converted to cefditoren and pivalate in the body. Pivalate combines with L-carnitine and is excreted in the urine, which increases L-carnitine losses from the body. Short courses of cefditoren can decrease blood concentrations of L-carnitine, but tissue levels are unlikely to be affected. Treatment for 1-2 months may cause a decrease in muscle L-carnitine, and treatment for 6 months or longer may cause symptoms of L-carnitine deficiency. Routine L-carnitine supplementation is not necessary unless therapy is prolonged or the patient has other factors contributing to low L-carnitine stores.
Taking Cefditoren Pivoxil? Monitor for depletion; a supplement is needed for some patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Here is something worth knowing about cefditoren pivoxil: when your body processes this antibiotic, it releases a byproduct called pivalate, which latches onto L-carnitine (a nutrient your muscles and heart use to turn fat into energy) and carries it out through the urine. A short course is unlikely to cause much trouble, but if you end up on this medication for several weeks or longer, carnitine levels in your muscles can drop enough to matter. If your therapy is prolonged or you already have low carnitine stores for other reasons, it is worth asking your pharmacist or doctor whether a supplement makes sense for you.

References (1)
  1. Brass EP. Pivalate-generating prodrugs and carnitine homeostasis in man. Pharmacol Rev 2002;54:589-98. PubMed

Full nutrient report for Cefditoren Pivoxil →

Pivampicillin

Moderate Depletion

Brand names include Pondicillin

Theoretically, L-carnitine levels may be reduced in patients taking pivampicillin.

This antibiotic is a prodrug which liberates the active antibiotic and pivalate in the body. Pivalate combines with L-carnitine and is excreted in the urine, which increases L-carnitine losses from the body. Short courses of pivampicillin decrease blood concentrations of L-carnitine, but tissue levels appear to be unaffected. Treatment for 1-2 months causes decrease in muscle L-carnitine, and treatment for 6 months or longer may cause symptoms of L-carnitine deficiency. Routine L-carnitine supplementation is not necessary unless therapy is prolonged, or the patient has other factors contributing to low L-carnitine stores.
Taking Pivampicillin? Monitor for depletion; a supplement is needed for some patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Here is something worth knowing about long-term pivampicillin use: when your body processes this antibiotic, it releases a byproduct called pivalate, which latches onto L-carnitine (a compound your muscles and heart depend on for energy) and carries it out through the urine. Short courses generally do not cause a real problem, but after several months the loss can start to affect muscle carnitine stores. If you are on this antibiotic for an extended period, it is worth asking your pharmacist or doctor whether a carnitine supplement makes sense for you.

References (2)
  1. Holme E, Greter J, Jacobson CE, et al. Carnitine deficiency induced by pivampicillin and pivmecillinam therapy. Lancet 1989;2:469-73. PubMed
  2. Brass EP. Pivalate-generating prodrugs and carnitine homeostasis in man. Pharmacol Rev 2002;54:589-98. PubMed

Full nutrient report for Pivampicillin →

Pivmecillinam

Moderate Depletion

Brand names include Selexid

Theoretically, L-carnitine levels may be reduced in patients taking pivmecillinam.

This antibiotic is a prodrug which liberates the active antibiotic and pivalate in the body. Pivalate combines with L-carnitine and is excreted in the urine, which increases L-carnitine losses from the body. Short courses of pivmecillinam decrease blood concentrations of L-carnitine, but tissue levels appear to be unaffected. Treatment for 1-2 months causes decrease in muscle L-carnitine, and treatment for 6 months or longer may cause symptoms of carnitine deficiency. Routine L-carnitine supplementation is not necessary unless therapy is prolonged, or the patient has other factors contributing to low L-carnitine stores.
Taking Pivmecillinam? Monitor for depletion; a supplement is needed for some patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

Here is something worth knowing about pivmecillinam: as your body processes this antibiotic, it releases a byproduct called pivalate, and pivalate latches onto L-carnitine (a nutrient your muscles and cells use to turn fat into energy) and carries it out through your urine. A short course usually does not cause meaningful problems because tissue levels stay relatively normal, but longer treatment of several months or more can gradually deplete muscle carnitine to the point of symptoms. If your course is brief, there is generally no action needed, but if you are on this antibiotic for an extended period, it is worth asking your pharmacist or doctor whether carnitine levels should be checked or a supplement makes sense for you.

References (2)
  1. Holme E, Greter J, Jacobson CE, et al. Carnitine deficiency induced by pivampicillin and pivmecillinam therapy. Lancet 1989;2:469-73. PubMed
  2. Brass EP. Pivalate-generating prodrugs and carnitine homeostasis in man. Pharmacol Rev 2002;54:589-98. PubMed

Full nutrient report for Pivmecillinam →

Sodium valproate

Moderate Depletion

Brand names include Epilim

L-carnitine levels may be reduced in patients taking valproate.

Valproic acid can reduce blood and tissue carnitine levels. Valproic acid interferes with L-carnitine biosynthesis in the liver, and formation of a valproylcarnitine ester which is excreted in the urine, reducing tubular reabsorption of free carnitine. Reduced L-carnitine levels are not clinically significant in most people taking valproic acid. However, some patients may be at increased risk for L-carnitine deficiency with valproic acid, and this may contribute to the development of hyperammonemia and hepatotoxicity associated with the drug. Risk factors for symptomatic L-carnitine deficiency with valproic acid include age less than 2 years, severe neurological problems including mental retardation, taking multiple antiepileptic drugs, poor nutrition, and use of the ketogenic diet. Some experts recommend L-carnitine supplements for people with these risk factors who need to take valproic acid. However, carnitine supplements aren't necessary for most people taking valproic acid who are otherwise healthy and consuming a diet adequate in L-carnitine.
Taking Sodium valproate? Monitor for depletion; a supplement is needed for some patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to move fatty acids into cells for energy production, and sodium valproate can lower your levels through two routes: it partially blocks the liver from making carnitine on its own, and it bonds to carnitine to form a byproduct that gets flushed out in the urine instead of being recycled by the kidneys. For most adults on valproate, this drop is not clinically significant and no action is needed. That said, certain people face a higher risk, including young children, those on multiple seizure medications, or anyone with poor nutrition, and for them a carnitine supplement may genuinely be warranted. If any of those risk factors apply to you, it is worth bringing up with your pharmacist or doctor.

References (17)
  1. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  2. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  3. Riva R, Albani F, Gobbi G, et al. Carnitine disposition before and during valproate therapy in patients with epilepsy. Epilepsia 1993;34:184-7. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed
  6. De Vivo DC, Bohan TP, Coulter DL, et al. L-carnitine supplementation in childhood epilepsy: Current perspectives. Epilepsia 1998;39:1216-25.
  7. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  8. Shapira Y, Gutman A. Muscle carnitine deficiency in patients using valproic acid. J Pediatrics 1991;118:646-9. PubMed
  9. Winter SC, Szabo-Aczel S, Curry CJR, et al. Plasma carnitine deficiency: Clinical observations in 51 pediatric patients. Am J Dis Child 1987;141:660-5. PubMed
  10. Cattaneo CI, Ressico F, Valsesia R, D'Innella P, Ballabio M, Fornaro M. Sudden valproate-induced hyperammonemia managed with L-carnitine in a medically healthy bipolar patient: Essential review of the literature and case report. Medicine (Baltimore). 2017 PubMed
  11. Coulter DL. Carnitine, valproate, and toxicity. J Child Neurol 1991;6:7-14.
  12. Raskind JY, El-Chaar GM. The role of carnitine supplementation during valproic acid therapy. Ann Pharmacother 2000;34:630-8. PubMed
  13. Coulter DL. Prevention of hepatotoxicity recurrence with valproate monotherapy and carnitine. Ann Neurol 1988;24:301.
  14. Vance CK, Vance H, Winter SC, et al. Control of valproate-induced hepatotoxicity with carnitine. Ann Neurol 1989;26:456.
  15. Hirose S, Mitsudome A, Yasumoto S, et al. Valproate therapy does not deplete carnitine levels in otherwise healthy children. Pediatrics 1998;101:E9 (abstract). PubMed
  16. Van Wouwe JP. Carnitine deficiency during valproic acid treatment. Int J Vitam Nutr Res 1995;65:211-4.
  17. Freeman JM, Vining EPG, Cost S, Singhi P. Does carnitine administration improve the symptoms attributed to anticonvulsant medications? A double-blinded, crossover study. Pediatrics 1994;93:893-5. DOI

Full nutrient report for Sodium valproate →

Valproic Acid

Moderate Depletion

Brand names include Depakene, Depacon, Valproate

L-carnitine levels may be reduced in patients taking valproate.

Valproic acid can reduce blood and tissue carnitine levels. Valproic acid interferes with L-carnitine biosynthesis in the liver, and formation of a valproylcarnitine ester which is excreted in the urine, reducing tubular reabsorption of free carnitine. Reduced L-carnitine levels are not clinically significant in most people taking valproic acid. However, some patients may be at increased risk for L-carnitine deficiency with valproic acid, and this may contribute to the development of hyperammonemia and hepatotoxicity associated with the drug. Risk factors for symptomatic L-carnitine deficiency with valproic acid include age less than 2 years, severe neurological problems including mental retardation, taking multiple antiepileptic drugs, poor nutrition, and use of the ketogenic diet. Some experts recommend L-carnitine supplements for people with these risk factors who need to take valproic acid. However, carnitine supplements aren't necessary for most people taking valproic acid who are otherwise healthy and consuming a diet adequate in L-carnitine.
Taking Valproic Acid? Monitor for depletion; a supplement is needed for some patients. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to ferry fatty acids into cells for energy production, and valproic acid can chip away at your levels through two routes: it interferes with the liver's ability to make carnitine, and it chemically binds to carnitine and sends it out through the urine rather than letting the kidneys recycle it. For most adults on valproic acid this drop is not clinically significant, but certain patients, particularly young children, people on multiple seizure medications, or those with poor nutrition, may be at higher risk for a meaningful deficiency that could contribute to serious side effects. If any of those risk factors apply to you or someone in your care, it is worth bringing up with your pharmacist or doctor to see whether monitoring or supplementation makes sense.

References (17)
  1. Thom H, Carter PE, Cole GF, et al. Ammonia and carnitine concentrations in children treated with sodium valproate compared with other anticonvulsant drugs. Dev Med Child Neurol 1991;33:795-802. PubMed
  2. Hug G, McGraw CA, Bates SR, et al. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. PubMed
  3. Riva R, Albani F, Gobbi G, et al. Carnitine disposition before and during valproate therapy in patients with epilepsy. Epilepsia 1993;34:184-7. PubMed
  4. Zelnik N, Fridkis I, Gruener N. Reduced carnitine and antiepileptic drugs: cause relationship or co-existence? Acta Paediatr 1995;84:93-5. PubMed
  5. Opala G, Winter S, Vance C, et al. The effect of valproic acid on plasma carnitine levels. Am J Dis Child 1991;145:999-1001. PubMed
  6. De Vivo DC, Bohan TP, Coulter DL, et al. L-carnitine supplementation in childhood epilepsy: Current perspectives. Epilepsia 1998;39:1216-25.
  7. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. PubMed
  8. Shapira Y, Gutman A. Muscle carnitine deficiency in patients using valproic acid. J Pediatrics 1991;118:646-9. PubMed
  9. Winter SC, Szabo-Aczel S, Curry CJR, et al. Plasma carnitine deficiency: Clinical observations in 51 pediatric patients. Am J Dis Child 1987;141:660-5. PubMed
  10. Cattaneo CI, Ressico F, Valsesia R, D'Innella P, Ballabio M, Fornaro M. Sudden valproate-induced hyperammonemia managed with L-carnitine in a medically healthy bipolar patient: Essential review of the literature and case report. Medicine (Baltimore). 2017 PubMed
  11. Coulter DL. Carnitine, valproate, and toxicity. J Child Neurol 1991;6:7-14.
  12. Raskind JY, El-Chaar GM. The role of carnitine supplementation during valproic acid therapy. Ann Pharmacother 2000;34:630-8. PubMed
  13. Coulter DL. Prevention of hepatotoxicity recurrence with valproate monotherapy and carnitine. Ann Neurol 1988;24:301.
  14. Vance CK, Vance H, Winter SC, et al. Control of valproate-induced hepatotoxicity with carnitine. Ann Neurol 1989;26:456.
  15. Hirose S, Mitsudome A, Yasumoto S, et al. Valproate therapy does not deplete carnitine levels in otherwise healthy children. Pediatrics 1998;101:E9 (abstract). PubMed
  16. Van Wouwe JP. Carnitine deficiency during valproic acid treatment. Int J Vitam Nutr Res 1995;65:211-4.
  17. Freeman JM, Vining EPG, Cost S, Singhi P. Does carnitine administration improve the symptoms attributed to anticonvulsant medications? A double-blinded, crossover study. Pediatrics 1994;93:893-5. DOI

Full nutrient report for Valproic Acid →

Atorvastatin

Insufficient Evidence

Brand names include Atorvaliq

L-carnitine levels in the seminal fluids may be reduced in patients taking atorvastatin.

In clinical research, taking atorvastatin 10 mg daily for 5 months reduced seminal fluid levels of L-carnitine. The clinical significance of this finding is unclear.
Taking Atorvastatin? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to help turn fat into energy, and it also plays a role in sperm health and function. One small study found that atorvastatin lowered L-carnitine levels in seminal fluid, though researchers aren't sure exactly why this happens or whether it matters clinically. Because the evidence is very limited right now, this is more of a 'keep an eye on it' finding than a reason to worry. If you have specific concerns, it's worth bringing up with your doctor or pharmacist.

References (1)
  1. Pons-Rejraji H, Brugnon F, Sion B, Maqdasy S, Gouby G, Pereira B, Marceau G, Gremeau AS, Drevet J, Grizard G, Janny L, Tauveron I. Evaluation of torvastatin efficacy and toxicity on spermatozoa, accessory glands and gonadal hormones of healthy men: a pilo

Full nutrient report for Atorvastatin →

Atorvastatin Calcium

Insufficient Evidence

Brand names include Lipitor

L-carnitine levels in the seminal fluids may be reduced in patients taking atorvastatin.

In clinical research, taking atorvastatin 10 mg daily for 5 months reduced seminal fluid levels of L-carnitine. The clinical significance of this finding is unclear.
Taking Atorvastatin Calcium? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to help convert fat into energy, and it also plays a role in sperm health and function. One small study found that men taking atorvastatin had lower L-carnitine levels specifically in seminal fluid, though researchers aren't sure exactly why this happens or whether it matters clinically. Because the evidence is quite limited right now, this isn't something most people need to worry about, but if you have questions or concerns about fertility, it's worth bringing up with your doctor or pharmacist.

References (1)
  1. Pons-Rejraji H, Brugnon F, Sion B, Maqdasy S, Gouby G, Pereira B, Marceau G, Gremeau AS, Drevet J, Grizard G, Janny L, Tauveron I. Evaluation of torvastatin efficacy and toxicity on spermatozoa, accessory glands and gonadal hormones of healthy men: a pilo

Full nutrient report for Atorvastatin Calcium →

Ezetimibe, Atorvastatin

Insufficient Evidence

Brand names include Liptruzet

L-carnitine levels in the seminal fluids may be reduced in patients taking atorvastatin.

In clinical research, taking atorvastatin 10 mg daily for 5 months reduced seminal fluid levels of L-carnitine. The clinical significance of this finding is unclear.
Taking Ezetimibe, Atorvastatin? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to help convert fat into energy, and it also plays a role in sperm health and function. One small study found that men taking atorvastatin had lower L-carnitine levels in their seminal fluid after several months, though researchers are not sure exactly why this happens or whether the statin interferes with how the body produces or transports carnitine. Because the evidence is quite limited and the real-world impact is still unknown, this is more of a research curiosity than a proven concern right now. If you have questions about fertility or this finding, it is worth bringing up with your doctor or pharmacist.

References (1)
  1. Pons-Rejraji H, Brugnon F, Sion B, Maqdasy S, Gouby G, Pereira B, Marceau G, Gremeau AS, Drevet J, Grizard G, Janny L, Tauveron I. Evaluation of torvastatin efficacy and toxicity on spermatozoa, accessory glands and gonadal hormones of healthy men: a pilo

Full nutrient report for Ezetimibe, Atorvastatin →

Ifosfamide

Insufficient Evidence

Brand names include Ifex

L-carnitine levels may be reduced in patients taking ifosfamide.

Increased urinary losses of carnitine can occur during ifosfamide therapy. This might be due to binding of L-carnitine with a metabolite of ifosfamide. The clinical significance of this finding and the role of L-carnitine supplements in people treated with ifosfamide are unknown.
Taking Ifosfamide? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, and some research has found that ifosfamide may cause more of it to leave the body through the urine. One theory is that a byproduct the body makes from ifosfamide can bind to L-carnitine, pulling it out before it can be used. That said, the evidence here is still too limited to know whether this actually causes a problem in practice, so most patients do not need to act on this right now. If you have questions or concerns, it is worth bringing up with your oncologist or pharmacist.

References (2)
  1. Marthaler NP, Visarius T, Kupfer A, Lauterburg BH. Increased urinary losses of carnitine during ifosfamide chemotherapy. Cancer Chemother Pharmacol 1999;44:170-2. PubMed
  2. Schlenzig JS, Charpentier C, Rabier D, et al. L-carnitine: a way to decrease cellular toxicity of ifosfamide? Eur J Pediatr 1995;154:686-7. DOI

Full nutrient report for Ifosfamide →

Lamivudine, Zidovudine

Insufficient Evidence

Brand names include Combivir

Theoretically, L-carnitine levels may be reduced in patients taking zidovudine.

Low L-carnitine blood levels are found in some people with HIV infection. Zidovudine seems to exacerbate this, and can also lower muscle carnitine levels, which is linked to symptoms of myopathy. Zidovudine interferes with mitochondrial transport of L-carnitine into muscle cells. In vitro data suggest L-carnitine supplements might improve functioning of muscle cells affected by zidovudine, but there isn't enough evidence to recommend routine use of L-carnitine supplements for patients taking zidovudine.
Taking Lamivudine, Zidovudine? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your muscles depend on to convert fat into usable energy, and zidovudine (one of the two drugs in this combination) appears to interfere with how carnitine is transported into muscle cells. People with HIV sometimes already have lower carnitine levels, and zidovudine may make that situation worse. That said, the evidence here is still too limited to know whether this matters much in practice, so talk with your pharmacist or doctor before considering any supplement.

References (4)
  1. Mintz M. Carnitine in human immunodeficiency virus type 1 infection/acquired immune deficiency syndrome. J Child Neurol 1995;10:S40-4. DOI
  2. Dalakas MC, Leon-Monzon ME, Bernardini I, et al. Zidovudine-induced mitochondrial myopathy is associated with muscle carnitine deficiency and lipid storage. Ann Neurol 1994;35:482-7. PubMed
  3. Campos Y, Arenas J. Muscle carnitine deficiency associated with zidovudine-induced mitochondrial myopathy. Ann Neurol 1994;36:680-1. PubMed
  4. Georges B, Galland S, Rigault C, et al. Beneficial effects of L-carnitine in myoblastic C2C12 cells. Interaction with zidovudine. Biochem Pharmacol 2003;65:1483-8.. PubMed

Full nutrient report for Lamivudine, Zidovudine →

Pyrimethamine

Insufficient Evidence

Brand names include Daraprim

Theoretically, L-carnitine levels may be reduced in patients taking pyrimethamine.

A single case report describes symptomatic L-carnitine deficiency in a patient treated with pyrimethamine plus sulfadiazine which reversed when both drugs were stopped. The mechanism of this effect is not known and further data is needed before L-carnitine depletion can be linked to these drugs.
Taking Pyrimethamine? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, particularly for your muscles and heart. There is one old case report of a patient on pyrimethamine plus a second antibiotic developing a deficiency, but the mechanism is simply not understood, and the evidence is far too thin to draw firm conclusions. For most people taking pyrimethamine, this is not something to lose sleep over. If you have concerns, a quick conversation with your pharmacist or doctor is the right place to start.

References (1)
  1. Sekas G, Paul HS. Hyperammonemia and carnitine deficiency in a patient receiving sulfadiazine and pyrimethamine. Am J Med 1993;95:112-3. PubMed

Full nutrient report for Pyrimethamine →

Pyrimethamine, Sulfadoxine

Insufficient Evidence

Brand names include Fansidar

Theoretically, L-carnitine levels may be reduced in patients taking pyrimethamine.

A single case report describes symptomatic L-carnitine deficiency in a patient treated with pyrimethamine plus sulfadiazine which reversed when both drugs were stopped. The mechanism of this effect is not known and further data is needed before L-carnitine depletion can be linked to these drugs.
Taking Pyrimethamine, Sulfadoxine? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into usable energy, particularly for muscles and the heart. There is one older case report of a patient on pyrimethamine plus a related sulfa drug developing low L-carnitine levels, though exactly how these medications might interfere is still unknown. Because the evidence is really just a single report with no confirmed mechanism, this is considered theoretical at this point, and most people on this combination will not need to worry about it. That said, if you have any concerns about fatigue or muscle weakness while on this treatment, it is worth mentioning to your pharmacist or doctor.

References (1)
  1. Sekas G, Paul HS. Hyperammonemia and carnitine deficiency in a patient receiving sulfadiazine and pyrimethamine. Am J Med 1993;95:112-3. PubMed

Full nutrient report for Pyrimethamine, Sulfadoxine →

Sulfadiazine

Insufficient Evidence
Theoretically, L-carnitine levels may be reduced in patients taking sulfadiazine.

A single case report describes symptomatic L-carnitine deficiency in a patient treated with pyrimethamine plus sulfadiazine which reversed when both drugs were stopped. The mechanism of this effect is not known and further data is needed before L-carnitine depletion can be linked to these drugs.
Taking Sulfadiazine? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to turn fat into energy, and it plays a role in keeping muscles and nerves working properly. There is one old case report of low L-carnitine in a patient taking sulfadiazine alongside another antibiotic, but researchers still do not know how the drug might cause this or whether sulfadiazine alone is responsible. The evidence here is really too thin to draw firm conclusions, so most people taking sulfadiazine do not need to worry about this. That said, if you are on it long-term and have questions, it is always worth a quick conversation with your pharmacist or doctor.

References (1)
  1. Sekas G, Paul HS. Hyperammonemia and carnitine deficiency in a patient receiving sulfadiazine and pyrimethamine. Am J Med 1993;95:112-3. PubMed

Full nutrient report for Sulfadiazine →

Brand names include Triple Sulfoid, Terfonyl

Theoretically, L-carnitine levels may be reduced in patients taking sulfadiazine.

A single case report describes symptomatic L-carnitine deficiency in a patient treated with pyrimethamine plus sulfadiazine which reversed when both drugs were stopped. The mechanism of this effect is not known and further data is needed before L-carnitine depletion can be linked to these drugs.
Taking Sulfadiazine, Sulfamerazine, Sulfamethazine? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your body uses to convert fat into energy, and it plays a role in keeping muscles working properly. There is one published case report of a patient developing a carnitine deficiency while taking sulfadiazine alongside another antibiotic, but researchers do not yet know exactly why or how the drug might affect carnitine levels. Because the evidence here is really just a single report with no confirmed mechanism, this is considered theoretical at best. If you are a long-term user of these sulfa drugs and have concerns, it is worth bringing up with your pharmacist or doctor.

References (1)
  1. Sekas G, Paul HS. Hyperammonemia and carnitine deficiency in a patient receiving sulfadiazine and pyrimethamine. Am J Med 1993;95:112-3. PubMed

Full nutrient report for Sulfadiazine, Sulfamerazine, Sulfamethazine →

Sulfadiazine, Trimethoprim

Insufficient Evidence

Brand names include Coptin

Theoretically, L-carnitine levels may be reduced in patients taking sulfadiazine.

A single case report describes symptomatic L-carnitine deficiency in a patient treated with pyrimethamine plus sulfadiazine which reversed when both drugs were stopped. The mechanism of this effect is not known and further data is needed before L-carnitine depletion can be linked to these drugs.
Taking Sulfadiazine, Trimethoprim? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine helps your body convert fat into usable energy, and there is one old case report linking sulfadiazine (used together with another drug called pyrimethamine) to a drop in carnitine levels that went away when both medicines were stopped. The exact reason this might happen is not understood, and the evidence is really too thin to draw firm conclusions. For most people taking sulfadiazine or trimethoprim, this is not something to worry about right now, but if you have concerns or you are on long-term treatment, it is always reasonable to bring it up with your pharmacist or doctor.

References (1)
  1. Sekas G, Paul HS. Hyperammonemia and carnitine deficiency in a patient receiving sulfadiazine and pyrimethamine. Am J Med 1993;95:112-3. PubMed

Full nutrient report for Sulfadiazine, Trimethoprim →

Zidovudine

Insufficient Evidence

Brand names include Retrovir, Retrovir Injection

Theoretically, L-carnitine levels may be reduced in patients taking zidovudine.

Low L-carnitine blood levels are found in some people with HIV infection. Zidovudine seems to exacerbate this, and can also lower muscle carnitine levels, which is linked to symptoms of myopathy. Zidovudine interferes with mitochondrial transport of L-carnitine into muscle cells. In vitro data suggest L-carnitine supplements might improve functioning of muscle cells affected by zidovudine, but there isn't enough evidence to recommend routine use of L-carnitine supplements for patients taking zidovudine.
Taking Zidovudine? Insufficient evidence to rate; clinical significance is not known. ⓘ
Dr. Brian Staiger, Pharm.D explains

L-carnitine is a compound your muscles depend on to produce energy, and there is some evidence that zidovudine may interfere with how it gets transported into muscle cells, potentially lowering muscle carnitine levels over time. HIV infection itself can already affect carnitine levels, and zidovudine appears to add to that. That said, the evidence here is still quite limited, so researchers do not yet know how clinically meaningful this is for most people. If you have been on zidovudine long-term and have concerns about muscle symptoms, it is worth bringing up with your doctor or pharmacist.

References (4)
  1. Mintz M. Carnitine in human immunodeficiency virus type 1 infection/acquired immune deficiency syndrome. J Child Neurol 1995;10:S40-4. DOI
  2. Dalakas MC, Leon-Monzon ME, Bernardini I, et al. Zidovudine-induced mitochondrial myopathy is associated with muscle carnitine deficiency and lipid storage. Ann Neurol 1994;35:482-7. PubMed
  3. Campos Y, Arenas J. Muscle carnitine deficiency associated with zidovudine-induced mitochondrial myopathy. Ann Neurol 1994;36:680-1. PubMed
  4. Georges B, Galland S, Rigault C, et al. Beneficial effects of L-carnitine in myoblastic C2C12 cells. Interaction with zidovudine. Biochem Pharmacol 2003;65:1483-8.. PubMed

Full nutrient report for Zidovudine →

Important

This tool is educational and is not a substitute for professional medical advice. An association is not a diagnosis and does not mean a deficiency will occur. Always talk to your pharmacist or healthcare provider before starting, stopping, or changing any medication or supplement.

Disclaimer: This checker finds which nutrients might be depleted by prescription or over-the-counter medications. Each nutrient depletion issue is rated based on clinical significance. Use your own professional judgment prior to making clinical decisions.

© 2026 Therapeutic Research Center Licensed records refresh weekly · last updated July 3, 2026.
Understand the basics

What drug-induced nutrient depletion means

Some medications can, over time, lower the levels of certain vitamins, minerals, or other nutrients — through reduced absorption, increased loss, or changes in how the body uses them.

Association is not deficiency

An entry here means a depletion has been reported or studied — not that it happens to everyone, or that you are deficient. Dose, duration, diet, and your own health all matter.

Evidence varies by pair

Some drug–nutrient links (like metformin and vitamin B12) are well studied; others rest on limited or preliminary research. Each entry shows the evidence rating from our licensed clinical database.

When to ask about labs

If you take an associated medication long-term, ask your healthcare provider whether monitoring is appropriate for you. Not everyone needs testing — your provider can weigh your dose, duration, and symptoms.

Don't self-supplement blindly

Supplements are not risk-free: some can interact with medications, and some (like potassium or magnesium) can be risky with kidney disease. Talk to your pharmacist before adding anything.

Never stop a medication over this

These medications are prescribed for good reasons, and the benefit usually far outweighs a manageable nutrient consideration. Any change belongs in a conversation with your prescriber.

Food first, usually

For many nutrients, a varied diet covers the gap. Each entry lists common food sources; a supplement is a decision to make with your pharmacist or provider, not a default.

Common questions

L-CARNITINE & medications: FAQs

Which medications can lower L-CARNITINE?
In our licensed clinical database, 49 medications have been associated with L-CARNITINE depletion, including Adefovir, Aprobarbital, Butabarbital, Phenobarbital, Aspirin, Codeine Phosphate, Phenobarbital and Atropine, Hyoscyamine, Phenobarbital. Each entry above shows the evidence rating and the published details. An association is not a guarantee — dose, duration, diet, and your own health all matter.
I take one of these medications — am I deficient in L-CARNITINE?
Not necessarily. These entries describe reported associations, not certainties. Many people take these medications without developing a meaningful L-CARNITINE problem. If you take one long-term, the reasonable step is to ask your healthcare provider whether checking your L-CARNITINE status is appropriate for you.
Should I start a L-CARNITINE supplement?
Not without checking first. Supplements are not risk-free — some interact with medications, and for certain nutrients (like potassium or magnesium) supplementation can be genuinely risky with kidney disease or particular drug combinations. Food-first strategies and clinician-guided testing usually come before a supplement.
Where does this information come from?
The depletion records come from the Natural Medicines (Therapeutic Research Center) database — an evidence-graded clinical reference — and are displayed as published, with their citations. The plain-English education is written and reviewed by licensed HelloPharmacist pharmacists.

Wondering about your L-CARNITINE levels?

Ask a licensed pharmacist — free, no appointment needed.

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Sources

Sources & How We Checked

Medication associations with L-CARNITINE are evidence-graded and sourced from the Natural Medicines database, and are displayed as published with their citations.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.