Pharmacist-built clinical tool

Does My Medication Cause Nutrient Depletion?

Some prescription and over-the-counter medications can lower your levels of important vitamins and minerals over time. Search your medication below to see what it may deplete — with evidence ratings and what to discuss with your pharmacist.

971Medications
32Nutrients
8,447Depletion records
Your results

Potential nutrient considerations for your selected medication

1 medication checked · 10 nutrients with reported associations. These are talking points for your care team — not a diagnosis.

ACETYL-L-CARNITINE

Insignificant Depletion

PHENOBARBITAL (Luminal)

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

Data on the effect of phenobarbital on blood levels of carnitines are conflicting. Some studies have found reduced L-carnitine levels in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine or acetyl-L-carnitine supplementation does not seem to be necessary.
Taking Phenobarbital, Sodium Nitrate? A supplement is not needed for most patients.
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

L-CARNITINE

Insignificant Depletion

PHENOBARBITAL (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, Sodium Nitrate? A supplement is not needed for most patients.
What Carnitine does & food sources

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

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

What to discuss with your clinician

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 — separate from the licensed record above.

Supplement considerations

Carnitine supplements are usually reserved for clinician-identified situations rather than general use.

Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

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

PROPIONYL-L-CARNITINE

Insignificant Depletion

PHENOBARBITAL (Luminal)

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

Data on the effect of phenobarbital on blood levels of carnitines are conflicting. Some studies have found reduced levels in some patients taking phenobarbital. However, other studies have found no significant effect. Routine L-carnitine or propionyl-L-carnitine supplementation does not seem to be necessary.
Taking Phenobarbital, Sodium Nitrate? A supplement is not needed for most patients.
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

BIOTIN

Moderate Depletion

PHENOBARBITAL (Luminal)

Phenobarbital might reduce blood levels of biotin.
Reduced plasma biotin levels can occur in people taking phenobarbital. In one study, plasma levels were 50% lower in people taking phenobarbital or various other anticonvulsants than in controls. There may also be increased urinary excretion of organic acids, an indicator of reduced biotin-dependent enzyme activity. Suggested mechanisms include competitive inhibition of biotin transport in the intestine, increased catabolism of biotin, and decreased renal tubular reabsorption of biotin. Phenobarbital contains a carbamide group, which is also present in biotin, and may lead to competition for intestinal and renal tubular absorption sites. The clinical significance of these effects on biotin isn't clear.
Taking Phenobarbital, Sodium Nitrate? Monitor for depletion; a supplement is needed for some patients.
References (7)
  1. Krause KH, Bonjour JP, Berlit P, Kochen W. Biotin status of epileptics. Ann N Y Acad Sci 1985;447:297-313.
  2. Krause KH, Kochen W, Berlit P, Bonjour JP. Excretion of organic acids associated with biotin deficiency in chronic anticonvulsant therapy. Int J Vitam Nutr Res 1984;54:217-22.
  3. Krause KH, Berlit P, Bonjour JP. Vitamin status in patients on chronic anticonvulsant therapy. Int J Vitam Nutr Res 1982;52:375-85.
  4. Mock DM, Dyken ME. Biotin deficiency results from long-term therapy with anticonvulsants (abstract). Gastroenterology 1995;108:A740. DOI
  5. Mock DM, Mock NI, Nelson RP, Lombard KA. Disturbances in biotin metabolism in children undergoing long-term anticonvulsant therapy. J Pediatr Gastroentereol Nutr 1998;26:245-50.
  6. Mock DM, Dyken ME. Biotin catabolism is accelerated in adults receiving long-term therapy with anticonvulsants. Neurology 1997;49:1444-7. PubMed
  7. Rathman SC, Eisenschenk S, McMahon RJ. The abundance and function of biotin-dependent enzymes are reduced in rats chronically administered carbamazepine. J Nutr 2002;132:3405-10. PubMed

CALCIUM

Moderate Depletion

PHENOBARBITAL (Luminal)

Taking phenobarbital decreases calcium absorption and increases calcium requirements.

Phenobarbital decreases calcium absorption by increasing metabolism of vitamin D, which is needed for calcium absorption. Hypocalcemia and osteomalacia have occurred, especially with prolonged therapy or when used in combination with carbamazepine and/or phenytoin. Advise patients taking phenytoin for six months or more that they may also need vitamin D and calcium supplements. For information on foods that are rich in calcium, see our chart.
Taking Phenobarbital, Sodium Nitrate? Monitor for depletion; a supplement is needed for some patients.
What Calcium does & food sources

Calcium builds and maintains bone and is essential for muscle contraction and nerve signaling.

Common food sources:

  • Dairy products (milk, yogurt, cheese)
  • Fortified plant milks and juices
  • Canned fish with bones (sardines, salmon)
  • Leafy greens like kale

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

What to discuss with your clinician

Ask your provider whether bone health monitoring (and vitamin D testing) makes sense with long-term use of an associated medication — a blood calcium level alone does not capture bone calcium status.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Supplement considerations

Calcium can interfere with the absorption of several medications (some antibiotics, thyroid medication, iron) — separate the doses and confirm timing with your pharmacist. Total intake from food plus supplements matters more than supplements alone.

Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Caution: Very high calcium intake has its own risks (kidney stones in susceptible people) — more is not better.

References (5)
  1. Gough H, Goggin T, Bissessar A, et al. A comparative study of the relative influence of different anticonvulsant drugs, UV exposure and diet on vitamin D and calcium metabolism in out-patients with epilepsy. Quart J Med 1986;59:569-77. DOI
  2. Hoikka V, Alhava EM, Karjalainen P, et al. Carbamazepine and bone mineral metabolism. Acta Neurol Scand 1984;70:77-80. PubMed
  3. Rajantie J, Lamberg-Allardt C, Wilska M. Does carbamazepine treatment lead to a need of extra vitamin D in some mentally retarded children? Acta Paediatr Scand 1984;73:325-8. PubMed
  4. Bell RD, Pak CY, Zerwekh J, et al. Effect of phenytoin on bone and mineral density in ambulatory epileptic children. Brain Dev 1994;16:382-5.
  5. Collins N, Maher J, Cole M, et al. A prospective study to evaluate the dose of vitamin D required to correct low 25-hydroxyvitamin D levels, calcium, and alkaline phosphatase in patients at risk of developing antiepileptic drug-induced osteomalacia. Q J M

FOLIC ACID

Moderate Depletion

PHENOBARBITAL (Luminal)

Phenobarbital can reduce serum folate levels and increase the risk of folate deficiency.

In people with low dietary folate intake, phenobarbital might reduce serum folate levels leading to megaloblastic anemia, and possibly contributing to neurological side effects, mental changes, and cerebral atrophy. Possible mechanisms include reduced folic acid absorption, increased metabolism, increased demand for folic acid as a coenzyme for induced hepatic enzymes, or competitive interaction between folate coenzymes and phenobarbital. Pregnant patients taking phenobarbital may be especially at risk for reduced folate levels, as low folate levels during pregnancy may contribute to birth defects and pregnancy loss. Folic acid therapy seems to reverse these neurological effects. However, folic acid can worsen seizure control. Advise patients taking phenobarbital to consult their physician before taking folic acid supplements. For information on foods that are rich in folate, see our chart.
Taking Phenobarbital, Sodium Nitrate? Monitor for depletion; a supplement is needed for some patients.
What Folic acid (folate) does & food sources

Folate is needed for cell division, red blood cell formation, and healthy fetal development.

Common food sources:

  • Leafy green vegetables
  • Beans, lentils, and peas
  • Fortified grains and cereals
  • Citrus fruits

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

What to discuss with your clinician

Ask your provider whether folate monitoring or supplementation is appropriate for you — this matters most before and during pregnancy, and with long-term use of certain seizure or arthritis medications.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Supplement considerations

Folate needs are individual. With some medications (for example, methotrexate), folic acid is often prescribed deliberately on a specific schedule — follow your prescriber's instructions rather than adding your own.

Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Caution: High-dose folic acid can mask vitamin B12 deficiency, so the two are often evaluated together.

References (10)
  1. Froscher W, Maier V, Laage M, et al. Folate deficiency, anticonvulsant drugs, and psychiatric morbidity. Clin Neuropharmacol 1995;18:165-82. PubMed
  2. Taliani U, Camellini A, Bernardi P, et al. A clinical case of severe megaloblastic anemia during treatment with primidone. Acta Biomed Ateneo Parmense 1989;60:245-8.
  3. Lambie DG, Johnson RH. Drugs and folate metabolism. Drugs 1985;30:145-55. PubMed
  4. Botez MI, Peyronnard J, Berube L, Labrecque R. Relapsing neuropathy, cerebral atrophy and folate deficiency. Appl Neurophysiol 1979;42:171-83.. DOI
  5. Reynolds EH. Neurological aspects of folate and vitamin B12 metabolism. Clin Haematol 1976;5:661-96. DOI
  6. Reynolds EH. Folate metabolism and anticonvulsant therapy. Proc R Soc Med 1974;67:68.
  7. Reynolds EH, Trimble MR. Adverse neuropsychiatric effects of anticonvulsant drugs. Drugs 1985;29:570-81. PubMed
  8. Hiilesmaa VK, Teramo K, Granstrom ML, Bardy AH. Serum folate concentrations during pregnancy in women with epilepsy: relation to antiepileptic drug concentrations, number of seizures, and fetal outcome. Br Med J 1983;287:577-9. DOI
  9. Dansky LV, Rosenblatt DS, Andermann E. Mechanisms of teratogenesis: folic acid and antiepileptic therapy. Neurology 1992;42:32-42.
  10. Lewis DP, Van Dyke DC, Stumbo PJ, Berg MJ. Drug and environmental factors associated with adverse pregnancy outcomes. Part I: antiepileptic drugs, contraceptives, smoking, and folate. Ann Pharmacother 1998;32:802-17. PubMed

VITAMIN B12

Moderate Depletion

PHENOBARBITAL (Luminal)

Phenobarbital, especially when taken long-term, might reduce vitamin B12 absorption and increase the risk of deficiency.

In one case report, a 23-year-old male with epilepsy who was taking phenytoin with phenobarbital for two years presented with megaloblastic anemia due to severe decreases in vitamin B12 and folate levels. Theoretically, phenytoin and/or phenobarbital may have interfered with vitamin B12 absorption. Encourage patients to maintain adequate dietary vitamin B12 intake, and check folate and vitamin B12 status if symptoms of anemia develop. If considering alternatives, neither oxcarbazepine (Trileptal), levetiracetam (Keppra), nor valproate have been associated with reduced vitamin B12 levels. For information on foods that are rich in vitamin B12, see our chart.
Taking Phenobarbital, Sodium Nitrate? Monitor for depletion; a supplement is needed for some patients.
What Vitamin B12 does & food sources

Vitamin B12 supports red blood cell formation, nerve function, and DNA synthesis.

Common food sources:

  • Meat, poultry, and fish
  • Eggs and dairy products
  • Fortified cereals and nutritional yeast

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

What to discuss with your clinician

If you take an associated medication long-term, ask your healthcare provider whether checking a vitamin B12 level (sometimes with methylmalonic acid) is appropriate — especially if you notice fatigue, numbness, tingling, or memory changes.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Supplement considerations

B12 status is easy to check and low levels are usually straightforward to address, so testing before supplementing is often the sensible order. High-dose folic acid can mask a B12 deficiency, which is one reason B12 and folate questions are best sorted out together with your provider.

Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Caution: B12 deficiency can look like other conditions — do not self-diagnose from symptoms alone.

References (5)
  1. Reynolds EH, Hallpike JF, Phillips BM, et al. Reversible absorptive defects in anticonvulsant megaloblastic anemia. J Clin Pathol 1965;18:593-8.
  2. Rezaei S, Shab-Bidar S, Abdurahman AA, Djafarian K. Oxcarbazepine administration and the serum levels of homocysteine, vitamin B12 and folate in epileptic patients: A systematic review and meta-analysis. Seizure. 2017;45:87-94. PubMed
  3. Sharma TK, Vardey SK, Sitaraman S. Evaluate the Effect of Valproate Monotherapy on the Serum Homocysteine, Folate and Vitamin B12 Levels in Epileptic Children. Clin Lab. 2015;61(8):933-40. PubMed
  4. Mahdavi A, Naeini AA, Najafi M, Ghazvini M, Maracy M. Vitamin B12 and Folate Status in Patients with Epilepsy Under Levetiracetam Monotherapy. Int J Prev Med. 2019;10:32. PubMed
  5. Ozdemir O, Yakut A, Dinleyici EC, Aydogdu SD, Yarar C, Colak O. Serum asymmetric dimethylarginine (ADMA), homocysteine, vitamin B(12), folate levels, and lipid profiles in epileptic children treated with valproic acid. Eur J Pediatr. 2011;170(7):873-7.

VITAMIN D

Moderate Depletion

PHENOBARBITAL (Luminal)

Taking phenobarbital for 6 month or longer might reduce blood levels of vitamin D.
Phenobarbital increases hepatic metabolism of vitamin D to inactive compounds, thereby reducing calcium absorption. Hypocalcemia and osteomalacia have occurred, especially with prolonged therapy, concurrent use of other enzyme-inducing anticonvulsants, or when other risk factors for vitamin D deficiency are present. Patients taking phenobarbital for 6 months or more may need vitamin D and calcium supplements. Doses of vitamin D needed vary from 400-4000 IU daily. For information on foods that are rich in vitamin D, see our chart.
Taking Phenobarbital, Sodium Nitrate? Monitor for depletion; a supplement is needed for some patients.
What Vitamin D does & food sources

Vitamin D helps the body absorb calcium and supports bone, muscle, and immune health.

Common food sources:

  • Fatty fish (salmon, mackerel)
  • Fortified milk and cereals
  • Egg yolks
  • Sunlight exposure (the main natural source)

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

What to discuss with your clinician

A 25-hydroxyvitamin D blood test is the standard way to assess status — ask whether it is appropriate if you take an associated medication long-term, have limited sun exposure, or have bone concerns.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Supplement considerations

Vitamin D dosing varies a lot between people; some medications change how vitamin D is processed. Your provider can target a dose to your level instead of guessing.

Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Caution: Vitamin D is fat-soluble and can accumulate — very high doses over time can cause harm, so follow a clinician-guided plan.

References (5)
  1. Gough H, Goggin T, Bissessar A, et al. A comparative study of the relative influence of different anticonvulsant drugs, UV exposure and diet on vitamin D and calcium metabolism in out-patients with epilepsy. Quart J Med 1986;59:569-77. DOI
  2. Hoikka V, Alhava EM, Karjalainen P, et al. Carbamazepine and bone mineral metabolism. Acta Neurol Scand 1984;70:77-80. PubMed
  3. Rajantie J, Lamberg-Allardt C, Wilska M. Does carbamazepine treatment lead to a need of extra vitamin D in some mentally retarded children? Acta Paediatr Scand 1984;73:325-8. PubMed
  4. Bell RD, Pak CY, Zerwekh J, et al. Effect of phenytoin on bone and mineral density in ambulatory epileptic children. Brain Dev 1994;16:382-5.
  5. Collins N, Maher J, Cole M, et al. A prospective study to evaluate the dose of vitamin D required to correct low 25-hydroxyvitamin D levels, calcium, and alkaline phosphatase in patients at risk of developing antiepileptic drug-induced osteomalacia. Q J M

VITAMIN E

Moderate Depletion

PHENOBARBITAL (Luminal)

Phenobarbital might reduce vitamin E levels.

There is some evidence that children taking phenobarbital have serum vitamin E levels 9% to 26% lower than children with untreated epilepsy. The clinical significance of this effect isn't clear. Vitamin E supplements don't seem to be harmful in children with epilepsy. They've been associated with either no effect on seizure control, or improved seizure control. Advise patients to maintain the recommended dietary intake of vitamin E. Consider supplements if plasma vitamin E levels are low (below 5 micrograms/mL).
Taking Phenobarbital, Sodium Nitrate? Monitor for depletion; a supplement is needed for some patients.
What Vitamin E does & food sources

Vitamin E is a fat-soluble antioxidant that protects cell membranes.

Common food sources:

  • Vegetable oils
  • Nuts and seeds
  • Wheat germ
  • Leafy greens

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

What to discuss with your clinician

Deficiency is rare; ask your provider before supplementing, particularly if you take blood thinners.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Supplement considerations

Higher-dose vitamin E can increase bleeding tendency, especially with warfarin or antiplatelet medications.

Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Caution: Discuss vitamin E supplements with your provider if you take any blood thinner.

References (6)
  1. Ogunmekan AO. Relationship between age and vitamin E level in epileptic children and normal children. Am J Clin Nutr 1979;32:2269-71.
  2. Kataoka K, Kanamori N, Oishi M, et al. Vitamin E status in pediatric patients receiving antiepileptic drugs. Devel Pharmacol Ther 1989;14:96-101. DOI
  3. Ogunmekan AO. Plasma vitamin E (alpha-tocopherol) levels in normal children and in epileptic children with and without anticonvulsant drug therapy. Trop Geog Med 1985;37:175-7.
  4. Higashi A, Ikeda T, Matsukura M, Matsuda I. Serum zinc and vitamin E concentrations in handicapped children treated with anticonvulsants. Devel Pharmacol Ther 1982;5:109-13. DOI
  5. Higashi A, Tamari H, Ikeda T, et al. Serum vitamin E concentration in patients with severe multiple handicaps treated with anticonvulsants. Pediatr Pharmacol 1980;1:129-34.
  6. Ogunmekan AO, Hwang PA. A randomized, double-blind, placebo-controlled, clinical trial of D-alpha-tocopheryl acetate (vitamin E), as add-on therapy, for epilepsy in children. Epilepsia 1989;30:84-9.

RIBOFLAVIN

Insufficient Evidence

PHENOBARBITAL (Luminal)

Phenobarbital might reduce active riboflavin levels; however, the clinical significance of this is unclear.
Some evidence in animals suggests that phenobarbital induces metabolism of riboflavin in the liver. Levels of the active form of riboflavin, flavin adenine dinucleotide (FAD), are increased in the liver and levels of a hydroxylated metabolite are increased in the urine. Also, some animal research suggests that phenobarbital does not significantly affect the content of flavin in the liver.
Taking Phenobarbital, Sodium Nitrate? Insufficient evidence to rate; clinical significance is not known.
What Vitamin B2 (riboflavin) does & food sources

Riboflavin helps the body produce energy and process other B vitamins.

Common food sources:

  • Dairy products and eggs
  • Lean meats
  • Fortified grains
  • Green vegetables

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

What to discuss with your clinician

Deficiency is uncommon with a varied diet; ask your provider if you have persistent mouth-corner cracking, sore tongue, or unexplained fatigue on a long-term associated medication.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

Supplement considerations

Riboflavin is water-soluble and excess is excreted (it turns urine bright yellow — harmless).

Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.

HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.

References (3)
  1. Ohkawa H, Ohishi N, Yagi K. Hydroxylation of the 7- and 8-methyl groups of riboflavin by the microsomal electron transfer system of rat liver. J Biol Chem 1983;258:5629-33.. DOI
  2. Hamajima S, Ono S, Hirano H, Obara K. Induction of the FAD synthetase system in rat liver by phenobarbital administration. Int J Vit Nutr Res 1979;49:59-63..
  3. Shargel L, Mazel P. Effect of riboflavin deficiency on phenobarbital and 3-methylcholanthrene induction of microsomal drug-metabolizing enzymes of the rat. Biochem Pharmacol. 1973;22(19):2365-73. PubMed
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

Nutrient depletion FAQs

Can medications really deplete nutrients?
Yes — some medications can lower levels of certain vitamins, minerals, or other nutrients over time, by reducing absorption, increasing loss through the kidneys or gut, or changing how the body uses them. Well-known examples include metformin (vitamin B12) and proton pump inhibitors like omeprazole (magnesium and B12). How much it matters varies a lot between medications and between people.
Does an entry in this checker mean I am deficient?
No. An entry means a depletion has been reported or studied with that medication — it does not mean it happens to everyone, or that it has happened to you. Dose, how long you have taken the medication, your diet, and your overall health all influence the actual risk. Think of the results as conversation starters for your pharmacist or doctor, not a diagnosis.
Should I take a supplement if my medication appears here?
Not automatically. Supplements are not risk-free — some interact with medications (for example, calcium, magnesium, iron, and zinc can reduce absorption of certain antibiotics and thyroid medication), and some can be risky in kidney disease. The better first step is usually to ask your healthcare provider whether testing or dietary changes make sense for you.
What labs should I ask about?
It depends on the nutrient. Some, like vitamin B12, vitamin D, potassium, magnesium, and sodium, have routine blood tests; others, like CoQ10, are not usually tested in everyday practice. Each nutrient entry in this tool notes what is commonly discussed. Your provider can decide whether testing is appropriate — routine testing is not necessary for everyone.
Can supplements interact with my medications?
Yes — that is one of the main reasons not to start supplements blindly. Interactions can change how much of a medication your body absorbs or how it works. You can check specific products and ingredients against your medications with our drug–supplement interaction checker, and confirm anything important with your pharmacist.
Where does this information come from, and how is it reviewed?
The depletion records come from the Natural Medicines (Therapeutic Research Center) database — an evidence-graded clinical reference used by pharmacists and clinicians — and are displayed as published, with their evidence ratings and citations. The surrounding plain-English education is written and reviewed by licensed HelloPharmacist pharmacists.

Not sure what your results mean?

Ask a licensed pharmacist — free, no appointment needed.

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Sources

Sources & How We Checked

Nutrient depletion records are evidence-graded and sourced from the Natural Medicines database, and are displayed as published with their citations. The plain-English education is written and reviewed by licensed HelloPharmacist pharmacists.

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