Health Guide


What is it?

L-carnitine is an amino acid used as a supplement for heart disease, athletic performance, weight loss, chronic fatigue, and poor circulation (also called intermittent claudication). L-carnitine may also be used to decrease the amount of cholesterol, also called fat, in your blood.

Other names for L-carnitine include: levocarnitine.

Ask your doctor, nurse, or pharmacist if you need more information about this medicine or if any information in this leaflet concerns you.

Before Using:

Tell your doctor if you ...

  • are taking medicine or are allergic to any medicine (prescription or over-the-counter (OTC) or dietary supplement)
  • are pregnant or plan to become pregnant while using this medicine
  • are breast feeding
  • have any other health problems, such as high blood pressure or heart or blood vessel disease


Talk with your doctor, pharmacist, or nurse about how much L-carnitine you should take. The amount depends on the strength of the medicine and the reason you are taking L-carnitine. If you are using this medicine without instructions from your caregiver, follow the directions on the label. Do not take more L-carnitine or take it more often than what is written on the directions.

To store this medicine:

Keep all medicine locked up and away from children. Store medicine away from heat and direct light. Do not store your medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down and not work the way it should work. Throw away medicine that is out of date or that you do not need. Never share your medicine with others.

Drug and Food Interactions:

Do not take L-carnitine without talking to your doctor first if you are taking:

  • Acenocoumarol (9,14)


  • Before taking L-carnitine, tell your doctor if you are pregnant or breastfeeding

Side Effects:

Stop taking your medicine right away and talk to your doctor if you have any of the following side effects.

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing, or rash.

Other Side Effects:

You may have the following side effects, but this medicine may also cause other side effects. Tell your doctor if you have side effects that you think are caused by this medicine.

  • Diarrhea and nausea (2,15)


1. Brevetti G, Chiariello M, Ferulano G et al: Increases in walking distance in patients with peripheral vascular disease treated with L-carnitine: a double-blind, cross-over study. Circulation 1988; 77(4): 767-773.

2. Campos Y, Huertas R, Lorenzo G et al: Plasma carnitine insufficiency and effectiveness of L-carnitine therapy in patients with mitochondrial myopathy. Muscle Nerve 1993; 16(2): 150-153.

3. Cherchi A, Lai C, Angelino Fet al: Effects of L-carnitine on exercise tolerance in chronic stable angina: A multicenter, double blind, randomized, placebo controlled crossover study. Int J Clin Pharm Ther Tox 1985; 23:569-572.

4. Crayhorn R: The carnitine miracle: the supernutrient program that promotes high energy, fat burning, heart health, brain wellness, and longevity. M Evans & Co, New York, NY; 1998.

5. Dal Negro R, Zoccatelli D, Pomari C et al: L-carnitine and physiokinesiotherapy in chronic respiratory insufficiency. Clin Trials J 1985; 22(4):353-360.

6. Davini P, Bigalli A, Lamanna F et al: Controlled study on L-carnitine therapeutic efficacy in post-infarction. Drugs Exp Clin Res 1992;18:355-365.

7. Iliceto S, Domenico S, Paolo B et al: Effects of L-carnitine administration on left ventricular remodeling after acute anterior myocardial infarction: The L-Carnitine Ecocardiografia Difitalizzata Intfarto Miocardico (CEDIM) trial. J AM Coll Cardiol 1995;26:380-387.

8. Kamikawa T, Yoshikazu S, Kobayashi A et al: Effects of L-carnitine on exercise tolerance in patients with stable angina pectoris. Jap Heart J 1984; 25:587-597.

9. Martinez E, Domingo P & Roca-Cusachs A: Potentiation of acenocoumarol action by L-carnitine (letter). J Intern Med 1993; 233:94.

10. Pistone G, Marino AD, Leotta C et al: Levocarnitine administration in elderly subjects with rapid muscle fatigue: effect on body composition, lipid profile and fatigue. Drugs Aging 2003; 20(10):761-767.

11. Plioplys A & Plioplys S: Amantadine and L-carnitine treatment of chronic fatigue syndrome. Neuropsychobiology 1997; 35(1): 16-23.

12. Sirtori CR, Calabresi L, Ferrara S et al: L-carnitine reduces plasma lipoprotein(a) levels in patients with hyperLp(a). Nutr Metab Cardiovasc Dis 2000; 10(5):247-251.

13. Swart I, Rossouw J, Loots J et al: The effect of L-carnitine supplementation on plasma carnitine levels and various performance parameters of male marathon athletes. Nutr Res 1997; 17(3):405-414.

14. Bachmann HU & Hoffman A: Interaction of food supplement L-carnitine with oral anticoagulant acenocoumarol. Swiss Med Wkly 2004; 134: 385.

15. Villani RG, Gannon J, Self M et al: L-carnitine supplementation combined with aerobic training does not promote weight loss in moderately obese women. Int J Sport Nutr Exerc Metab 2000; 10(2):199-207.

Last Updated: 7/4/2018
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