Drug & supplement interaction

L-carnitine + Dupilumab

Dupilumab brand name: Dupixent.

No Known Interaction
The bottom line No known interaction

We found no known interaction between L-carnitine and Dupilumab in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

L-carnitine and Dupilumab

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Dupilumab and L-carnitine in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

L-carnitine safety at a glance

L-carnitine overall Use caution Generally well tolerated at typical doses, but high doses can cause stomach upset and a fishy body odor.
Pregnancy Use caution Not enough reliable safety data; use only under medical supervision.
Breastfeeding Possibly Safe When used orally. Supplemental doses of L-carnitine have been given to infants in breast milk and formula with no reported adverse effects. The effects of large... Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Dupilumab and L-carnitine? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
Keep it in perspective

L-carnitine Does Interact With Other Medications

L-carnitine has 19 moderate known drug interactions in our database — Dupilumab isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against L-carnitine

Covers the 2,830 medications we’ve checked against L-carnitine. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests L-carnitine and Dupilumab May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • Itching / A skin rash reported in 17.5% of FDA reports for Dupilumab Additional detail

    L-carnitine

    “Orally, L-carnitine has been reported to cause skin rash in a small number of cases.

    Two patients in a hair growth study using topical carnitine reported mild itching and increased dandruff, while a third reported strong itching with reddish bumps and a burning sensation.”

    L-carnitine · Natural Medicines adverse-effect record, reported in pruritus.

    4 sources cited
    1. 16105. 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
    2. 91724. 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
    3. 58390. 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
    4. 26493. 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

    Dupilumab

    Listed in the ADVERSE REACTIONS section of the FDA label for Dupilumab, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

  • Stomach upset / Diarrhea Additional detail

    L-carnitine

    “Orally and intravenously, L-carnitine has been associated with nausea, epigastric discomfort, vomiting, abdominal cramps, heartburn, gastritis, anorexia, and diarrhea. Orally, diarrhea or colitis symptoms, nausea and abdominal pain, indigestion, and constipation have been reported in various clinical trials.”

    L-carnitine · Natural Medicines adverse-effect record, reported in anorexia.

    6 sources cited
    1. 3616. Anon. Carnitor (levocarnitine) package insert. Sigma-Tau Pharmaceuticals Inc, Gaithersburg, MD. December 1999.
    2. 3624. 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.
    3. 59030. 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
    4. 95069. 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
    5. 95070. 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
    6. 101562. 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

    Dupilumab

    Listed in the ADVERSE REACTIONS section of the FDA label for Dupilumab. Read the label on DailyMed ›

  • Headache Additional detail

    L-carnitine

    “Orally or intravenously, L-carnitine has been associated with seizures. Orally, use of L-carnitine in clinical trials has resulted in headache, although this event is rare. L-carnitine may also cause agitation.”

    L-carnitine · Natural Medicines adverse-effect record, reported in cluster headache.

    4 sources cited
    1. 3616. Anon. Carnitor (levocarnitine) package insert. Sigma-Tau Pharmaceuticals Inc, Gaithersburg, MD. December 1999.
    2. 58554. 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
    3. 95070. 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
    4. 111891. 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

    Dupilumab

    Listed in the ADVERSE REACTIONS section of the FDA label for Dupilumab. Read the label on DailyMed ›

Reported for L-carnitine but not commonly for Dupilumab: a heart attack, stomach pain, reduced appetite and heart failure.

Effects for Dupilumab come from the ADVERSE REACTIONS section of its FDA label; effects for L-carnitine come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 478,975 voluntary FDA FAERS reports for Dupilumab that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

L-carnitine in Pregnancy & Breastfeeding

Lactation Possibly Safe

When used orally. Supplemental doses of L-carnitine have been given to infants in breast milk and formula with no reported adverse effects. The effects of large doses used while nursing are unknown, but L-carnitine is secreted in the breast milk.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About L-carnitine or Dupilumab

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers L-carnitine or Dupilumab, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

One more smart check

Taking L-carnitine as Part of a Dietary Supplement Product? Check It for Interactions

We hold 3,350 real supplement products containing L-carnitine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides L-carnitine. Even though L-carnitine itself has no known interaction with Dupilumab, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where L-carnitine and Dupilumab Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement L-carnitine
Top 10%

#81 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Dupilumab
Steady interest

#1,985 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every L-carnitine reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The L-carnitine and Dupilumab records this page draws on were last updated July 11, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About L-carnitine

What is L-carnitine?

  • Exercise performance and recovery
  • Heart health
  • Weight management
  • Energy and fatigue
  • Male fertility
  • Carnitine deficiency

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 clearly useful for people with a true carnitine deficiency. For most other uses, like weight loss or boosting athletic performance, the evidence is mixed or limited, so talk with your pharmacist or doctor before trying it.

Capsules, tablets, oral liquid, powder, and injectable (prescription) forms

An interaction check asks whether these two react with each other — it does not ask whether L-carnitine is a good idea for someone in your situation. Here is what our L-carnitine record says about it on its own.

L-carnitine: dosing

There is no single standard dose of L-carnitine that fits everyone, and the right amount depends on the form and the reason for use. Prescription carnitine for true deficiency is dosed by a doctor based on medical needs.For over-the-counter supplements, the best approach is to follow the directions on the product label and not exceed the recommended amount.

From our L-carnitine monograph — the full record covers uses, side effects and every documented interaction.

Read the full L-carnitine monograph & all interactions
Medication

About Dupilumab Injection

What Is Dupilumab Injection Used For?

Brand name: Dupixent

Dupixent (dupilumab) injection is approved for several inflammatory conditions. It treats moderate-to-severe atopic dermatitis (eczema) in patients 6 months and older when topical treatments haven't worked well enough. It is also used as an add-on maintenance treatment for moderate-to-severe asthma (ages 6 and up), chronic rhinosinusitis with nasal polyps (ages 12 and up), and COPD with an eosinophilic phenotype in adults.

Additionally, Dupixent treats eosinophilic esophagitis (EoE, a chronic inflammatory condition of the esophagus) in patients 1 year and older weighing at least 15 kg, prurigo nodularis (severe itchy skin nodules) in adults, chronic spontaneous urticaria (hives without a clear trigger) in patients 2 and older who haven't responded to antihistamines, bullous pemphigoid (a blistering skin disease) in adults, and allergic fungal rhinosinusitis in patients 6 and older with a history of sinus surgery. It is not for relief of sudden or acute breathing attacks.

Most-Reported Side Effects for Dupilumab

From FAERS, the FDA’s public side-effect reporting system (478,975 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Pruritus 58,692 reports
Dermatitis atopic 45,026 reports
Rash 38,629 reports
Injection site pain 36,707 reports
Eczema 26,626 reports
See full Dupilumab Injection drug information
Keep checking

Other Drugs & L-carnitine

Browse every other medication we’ve checked against L-carnitine — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
19Moderate
0Minor
2,810No known interaction
Moderate

19 interactions

No interaction 2,810 drugs checked — show the list
Evidence & sources

L-carnitine References

The 41 references that drive our L-carnitine monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  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

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking L-carnitine and Dupilumab Together: Common Questions

Is it safe to take L-carnitine with Dupilumab?
We do not list a known interaction between L-carnitine and Dupilumab. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do L-carnitine and Dupilumab have any of the same side effects?
Yes — our sources link each of them separately to 5 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Does L-carnitine interact with any other medications?
Yes. L-carnitine has 19 documented drug interactions in our database — Dupilumab is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.

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

Still Have a Question About Dupilumab and L-carnitine?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.