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Dietary supplement

L-Carnitine HCl Ingredients & Drug Interactions

by BulkSupplements.com

Powder Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

L-Carnitine HCl is a dietary supplement by BulkSupplements.com with 1 active ingredient. Its ingredients are commonly taken for exercise performance and recovery, heart health, weight management.Based on those ingredients, 19 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-Carnitine Hydrochloride. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of L-Carnitine HCl by BulkSupplements.com

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: L-carnitine hydrochloride. L-carnitine is a naturally occurring compound that plays a role in how your body produces energy from fatty acids.

The supplement has no inactive ingredients listed — it's pure powder.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

This product doesn't appear to be marketed for a specific use, so we graded L-carnitine's overall clinical evidence instead.

Strong

Strong clinical evidence supports L-carnitine for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredient's overall clinical evidence instead.
  • On file: L-carnitine deficiency — rated "Effective" (Natural Medicines).
  • On file: Angina — rated "Possibly Effective" (Natural Medicines).
  • On file: Congestive heart failure (CHF) — rated "Possibly Effective" (Natural Medicines).
  • On file: Hyperlipidemia — rated "Possibly Effective" (Natural Medicines).
  • On file: Myocarditis — rated "Possibly Effective" (Natural Medicines).

The evidence for L-carnitine is strongest for treating L-carnitine deficiency itself, where it's rated effective. For other uses — high cholesterol (hyperlipidemia), congestive heart failure, and angina — the evidence is rated possibly effective, meaning there's some support but it's not conclusive.

Your condition and why you're considering this product will matter when deciding whether to try it.

The evidence, ingredient by ingredient L-carnitine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-carnitine is generally well tolerated at typical doses. The most common side effects are gastrointestinal: stomach cramps, pain, diarrhea, heartburn, nausea, and reduced appetite.

A fish-like body odor has also been reported. High doses may make these symptoms worse.

Rare serious side effects like seizures have been reported. There isn't enough reliable safety data for use in pregnancy, and safety while breastfeeding is not well studied, so caution is advised — talk with your doctor or pharmacist about whether this is right for you in either situation.

Side effects, ingredient by ingredient L-carnitine

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — L-carnitine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 19 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check your medications with the tool on this page if you're on blood thinners like warfarin or acenocoumarol — L-carnitine may increase their effects. Also check if you take thyroid hormone replacement, since L-carnitine may reduce its effectiveness.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

L-carnitine may help if you have a documented deficiency or certain heart conditions, but it's not for everyone. If you take blood thinners (warfarin, acenocoumarol) or thyroid medication, you need to check with your pharmacist first.

Start with the lowest dose to assess how your stomach handles it.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 23, 2024.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about L-Carnitine HCl, straight from the product label.

Brand BulkSupplements.com
Barcode (UPC) X0019M1H3N
Net contents 500 Gram(s); 17.6 Oz(s)
Market status On market
Date entered into DSLD May 23, 2024
DSLD ID 312107
Product type Non-nutrient/non-botanical
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for L-Carnitine HCl by BulkSupplements.com, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
500 mg
Maximum serving Sizes:
500 mg
Servings per container
1000
UPC/BARCODE
X0019M1H3N
IngredientAmount% DV
L-Carnitine Hydrochloride500 mg--

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Brand IP Statement(s)

BulkSupplements.com Clean & pure bulk supplements

FDA Disclaimer Statement

Warning: This product is not intended to diagnose, treat, cure, or prevent any disease.

Precautions

Always consult a physician before taking any dietary supplement.

Keep out of reach of children.

Formulation

Free of: Added sugar, soy, dairy, yeast, gluten, additives

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take 500 mg (about 1/5 tsp) one to four times daily, or as directed by a physician.

Storage

Store in a dry, cool place Contents are sold by weight, not volume. Settling may occur.

General Statements

New Use an accurate milligram scale.

See for yourself

L-Carnitine HCl by BulkSupplements.com label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

What’s inside

The Ingredients in L-Carnitine HCl by BulkSupplements.com

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size500 mg Dosage formPowder Servings per container1000 Amounts shown are per serving.

L-Carnitine Hydrochloride

Interacts with
19 drugs
500 mg per serving

L-carnitine is a compound your body makes naturally and also gets from foods like meat. It helps cells turn fat into energy, and supplements are most...

L-Carnitine Hydrochloride monograph & interactions
Interaction report

L-Carnitine HCl by BulkSupplements.com Drug Interactions

Want to check YOUR meds against L-Carnitine HCl?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
19Drugs
19 Moderate

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Carnitine HCl with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

L-Carnitine Hydrochloride3 drug types · 19 drugs

Acenocoumarol (Sintrom)

Theoretically, L-carnitine might increase the anticoagulant effects of acenocoumarol.
L-carnitine might enhance the anticoagulant effects of acenocoumarol, an oral anticoagulant similar to warfarin, but shorter-acting. There are at least two case reports of INR elevation with concomitant use. In one case, a 33-year-old male with a previously stable INR had an elevated INR of 4.65 after L-carnitine was started and continued for 10 weeks. INR normalized after discontinuation of the L-carnitine-containing product.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, L-carnitine might decrease the effectiveness of thyroid hormone replacement.
L-carnitine appears to act as a peripheral thyroid hormone antagonist by inhibiting entry of thyroid hormone into the nucleus of cells. Taking L-carnitine also seems to diminish some of the symptoms of hyperthyroidism.

Likelihood Probable Evidence B
Warfarin (Coumadin)

Theoretically, L-carnitine might increase the anticoagulant effects of warfarin.
L-carnitine might increase the anticoagulant effects of acenocoumarol, a shorter-acting oral anticoagulant similar to warfarin. There is not enough information to know whether this interaction occurs with L-carnitine and warfarin.

Likelihood Possible Evidence D
The maker

Brand information

Manufacturer and brand details for L-Carnitine HCl, from the product label.

BulkSupplements.com

See all BulkSupplements.com products
Name
BulkSupplements.com
Street Address
7511 Eastgate Rd
City
Henderson
State
NV
ZipCode
89011
Web Address
BulkSupplements.com
Pharmacist Counseling Corner

L-Carnitine HCl by BulkSupplements.com: Common Questions

Does L-Carnitine HCl by BulkSupplements.com interact with any medications?
Yes. Based on its ingredients, L-Carnitine HCl has a known interaction with 19 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Carnitine HCl contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What does L-carnitine do in my body?
L-carnitine helps your body produce energy from fatty acids. It's especially important if your body doesn't make enough on its own, which is called L-carnitine deficiency.
Will L-carnitine help my cholesterol or heart condition?
The evidence suggests it may help with high cholesterol, congestive heart failure, and angina, but it's not definitive — it's rated possibly effective for these uses. Talk with your doctor about whether it makes sense for you.
What are the most likely side effects?
Stomach upset is the main issue: cramps, pain, diarrhea, heartburn, nausea, and loss of appetite. High doses make these more likely. Some people also report a fish-like body odor.
Is L-carnitine safe during pregnancy or breastfeeding?
There isn't enough safety data in either situation. Talk with your doctor or pharmacist about whether it's right for you before taking it while pregnant or nursing.
Can I take this with my thyroid medication?
Not without checking first. L-carnitine may reduce how well your thyroid medication works by blocking it from entering your cells. Your pharmacist can help you figure out if it's safe for you.
Can I take this if I'm on a blood thinner?
You need to check with your pharmacist before starting. L-carnitine may increase the effects of blood thinners like warfarin and acenocoumarol, which could raise your bleeding risk.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if L-Carnitine HCl is safe with your meds?

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

L-Carnitine HCl label
Sources

Sources & How We Checked

L-Carnitine HCl's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our 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.

The 41 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

L-carnitine 41 references
  1. Ellaway CM, Williams K, Leonard H, et al. Rett syndrome: randomized controlled trial of L-carnitine. J Child Neurol 1999;14:162-7. PubMed
  2. Anon. Carnitor (levocarnitine) package insert. Sigma-Tau Pharmaceuticals Inc, Gaithersburg, MD. December 1999.
  3. Cherchi A, Lai C, Angelino F, et al. Effects of L-carnitine on exercise tolerance in chronic stable angina: a multicenter, double-blind, randomized, placebo-controlled, crossover study. Int J Clin Pharmacol Ther Toxicol 1985;23:569-72.
  4. Plioplys AV, Plioplys S. Amantadine and L-carnitine treatment of Chronic Fatigue Syndrome. Neuropsychobiology 1997;35:16-23. PubMed
  5. Benvenga S, Ruggeri RM, Russo A, et al. Usefulness of L-carnitine, a naturally occurring peripheral antagonist of thyroid hormone action, in iatrogenic hyperthyroidism: a randomized, double-blind, placebo-controlled clinical trial. J Clin Endocrinol Meta
  6. Martinez E, Domingo P, Roca-Cusachs A. Potentiation of acenocoumarol action by L-carnitine. J Intern Med 1993;233:94.
  7. Bachmann HU, Hoffmann A. Interaction of food supplement L-carnitine with oral anticoagulant acenocoumarol. Swiss Med Wkly 2004;134:385. PubMed
  8. Evans AM, Fornasini G. Pharmacokinetics of L-carnitine. Clin Pharmacokinet 2003;42:941-67. PubMed
  9. 12761 Benvenga S, Amato A, Calvani M, Trimarchi F. Effects of carnitine on thyroid hormone action. Ann N Y Acad Sci 2004;1033:158-67. PubMed
  10. Ciacci C, Peluso G, Iannoni E, et al. L-Carnitine in the treatment of fatigue in adult celiac disease patients: a pilot study. Dig Liver Dis 2007;39:922-8. PubMed
  11. Cruciani RA, Dvorkin E, Homel P, et al. Safety, tolerability and symptom outcomes associated with L-carnitine supplementation in patients with cancer, fatigue, and carnitine deficiency: a phase I/II study. J Pain Symptom Manage 2006;32:551-9. PubMed
  12. Lebrun C, Alchaar H, Candito M, et al. Levocarnitine administration in multiple sclerosis patients with immunosuppressive therapy-induced fatigue. Mult Scler 2006;12:321-4. PubMed
  13. Malaguarnera M, Cammalleri L, Gargante MP, et al. L-Carnitine treatment reduces severity of physical and mental fatigue and increases cognitive functions in centenarians: a randomized and controlled clinical trial. Am J Clin Nutr 2007;86:1738-44. PubMed
  14. Mantovani G, Maccio A, Madeddu C, et al. Randomized phase III clinical trial of five different arms of treatment in 322 patients with cancer cachexia. Oncologist 2010;15:200-11.
  15. Angelova-Fischer I, Rippke F, Fischer TW, Neufang G, Zillikens D. A double-blind, randomized, vehicle-controlled efficacy assessment study of a skin care formulation for improvement of mild to moderately severe acne. J Eur Acad Dermatol Venereol. 2013 Jul PubMed
  16. Hatamkhani S, Khalili H, Karimzadeh I, Dashti-Khavidaki S, Abdollahi A, Jafari S. Carnitine for prevention of antituberculosis drug-induced hepatotoxicity: a randomized, clinical trial. J Gastroenterol. Hepatol. 2014 May;29(5):997-1004. PubMed
  17. Boehm G, Stahl B. Oligosaccharides from milk. J Nutr 2007;137(3 Suppl 2):847S-849S.
  18. Van Oudheusden, L. J. and Scholte, H. R. Efficacy of carnitine in the treatment of children with attention-deficit hyperactivity disorder. Prostaglandins Leukot.Essent.Fatty Acids 2002;67(1):33-38. PubMed
  19. Derosa, G., Cicero, A. F., Gaddi, A., Mugellini, A., Ciccarelli, L., and Fogari, R. The effect of L-carnitine on plasma lipoprotein(a) levels in hypercholesterolemic patients with type 2 diabetes mellitus. Clin Ther 2003;25(5):1429-1439. PubMed
  20. Foitzik, K., Hoting, E., Heinrich, U., Tronnier, H., and Paus, R. Indications that topical L-carnitin-L-tartrate promotes human hair growth in vivo. J Dermatol.Sci 2007;48(2):141-144. PubMed
  21. Kumar, A., Singh, R. B., Saxena, M., Niaz, M. A., Josh, S. R., Chattopadhyay, P., Mechirova, V., Pella, D., and Fedacko, J. Effect of carni Q-gel (ubiquinol and carnitine) on cytokines in patients with heart failure in the Tishcon study. Acta Cardiol. 20
  22. Cruciani, R. A., Dvorkin, E., Homel, P., Culliney, B., Malamud, S., Lapin, J., Portenoy, R. K., and Esteban-Cruciani, N. L-carnitine supplementation in patients with advanced cancer and carnitine deficiency: a double-blind, placebo-controlled study. J Pa PubMed
  23. Malaguarnera, M., Vacante, M., Avitabile, T., Malaguarnera, M., Cammalleri, L., and Motta, M. L-Carnitine supplementation reduces oxidized LDL cholesterol in patients with diabetes. Am J Clin.Nutr 2009;89(1):71-76. PubMed
  24. Alvarez, T. M., Guardiola, P. D., Roldan, J. O., Elviro, R., Wevers, R., and Guijarro, G. [Primary trimethylaminuria: the fish odor syndrome]. Endocrinol.Nutr. 2009;56(6):337-340.
  25. Wu, Z. M., Lu, X., Wang, Y. W., Sun, J., Tao, J. W., Yin, F. H., and Cheng, H. J. [Short-term medication of L-carnitine before intracytoplasmic sperm injection for infertile men with oligoasthenozoospermia]. Zhonghua Nan.Ke.Xue 2012;18(3):253-256.
  26. Tarighat, Esfanjani A., Mahdavi, R., Ebrahimi, Mameghani M., Talebi, M., Nikniaz, Z., and Safaiyan, A. The effects of magnesium, L-carnitine, and concurrent magnesium-L-carnitine supplementation in migraine prophylaxis. Biol.Trace Elem.Res 2012;150(1-3): PubMed
  27. DiNicolantonio, J. J., Lavie, C. J., Fares, H., Menezes, A. R., and O'Keefe, J. H. L-carnitine in the secondary prevention of cardiovascular disease: systematic review and meta-analysis. Mayo Clin Proc. 2013;88(6):544-551. PubMed
  28. Huang, W. W., Wang, M. Y., Shi, H. M., Peng, Y., Peng, C. S., Zhang, M., Li, Y., Lu, J., and Li, X. B. Comparative study of bioactive constituents in crude and processed Glycyrrhizae radix and their respective metabolic profiles in gastrointestinal tract
  29. Madsen KL, Preisler N, Orngreen MC, Andersen SP, Olesen JH, Lund AM, Vissing J. Patients with medium-chain acyl-coenzyme a dehydrogenase deficiency have impaired oxidation of fat during exercise but no effect of L-carnitine supplementation. J Clin Endocri
  30. Prohaska ES, Muzyk AJ, Rivelli SK. Levocarnitine-induced hypophosphatemia in a hemodialysis patient with acute valproic acid toxicity. J Neuropsychiatry Clin Neurosci. 2012 Winter;24(1):E18-9. PubMed
  31. Shang R, Sun Z, Li H. Effective dosing of L-carnitine in the secondary prevention of cardiovascular disease: a systematic review and meta-analysis. BMC Cardiovasc Disord. 2014 Jul 21;14:88. PubMed
  32. Zhang JJ, Wu ZB, Cai YJ, Ke B, Huang YJ, Qiu CP, Yang YB, Shi LY, Qin J. L-carnitine ameliorated fasting-induced fatigue, hunger, and metabolic abnormalities in patients with metabolic syndrome: a randomized controlled study. Nutr J. 2014 Nov 26;13:110. PubMed
  33. Koeth RA, Wang Z, Levison BS, Buffa JA, Org E, Sheehy BT, Britt EB, Fu X, Wu Y, Li L, Smith JD, DiDonato JA, Chen J, Li H, Wu GD, Lewis JD, Warrier M, Brown JM, Krauss RM, Tang WH, Bushman FD, Lusis AJ, Hazen SL. Intestinal microbiota metabolism of L-carn
  34. Jun DW, Kim BI, Cho YK, Kim HJ, Kwon YO, Park SY, Han SY, Baek YH, Jung YJ, Kim HY, Kim W, Heo J, Woo HY, Hwang SG, Rim KS, Choi JY, Bae SH, Lee YS, Lim YS,Cheong JY, Cho SW, Lee BS, Kim SH, Sohn JH, Kim TY, Paik YH, Kim JK, Lee KS. Efficacy and safety of
  35. An JH, Kim YJ, Kim KJ, et al. L-carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: a randomized, double-blind, placebo-controlled trial. Endocr J. 2016;63(10):885-95. PubMed
  36. Chen N, Yang M, Zhou M, Xiao J, Guo J, He L. L-carnitine for cognitive enhancement in people without cognitive impairment. Cochrane Database Syst Rev. 2017;3:CD009374. PubMed
  37. Khajeh B, Dashti-Khavidaki S, Nasiri-Toosi M, Mohammadi K, Jafari A. Effects of pre-transplant L-carnitine supplementation on primary graft dysfunction in liver transplant recipients: a pilot, randomized, placebo-controlled clinical trial. Res Pharm Sci. PubMed
  38. Kubota K, Uojima H, Shao X, et al. Additional L-carnitine Reduced the Risk of Hospitalization in Patients with Overt Hepatic Encephalopathy on Rifaximin. Dig Dis 2021. PubMed
  39. Amini L, Yaghini O, Ghazavi M, Aslani N. L-carnitine versus propranolol for pediatric migraine prophylaxis. Iran J Child Neurol 2021;15(2):77-86.
  40. Shakibaei F, Jelvani D. Effect of adding l -carnitine to risperidone on behavioral, cognitive, social, and physical symptoms in children and adolescents with autism: A randomized double-blinded placebo-controlled clinical trial. Clin Neuropharmacol 2023;4 PubMed
  41. Moustafa I, Connolly C, Anis M, Mustafa H, Oosthuizen F, Viljoen M. A prospective study to evaluate the efficacy and safety of vitamin E and levocarnitine prophylaxis against doxorubicin-induced cardiotoxicity in adult breast cancer patients. J Oncol Phar PubMed

See these in context on the L-carnitine monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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