L-carnitine is an amino acid present in the body, in muscles and heart tissue. It plays a key role in fatty acid metabolism, allowing cells to access the energy they require. These functions make it popular in skincare formulations. But does topical L-carnitine carry any risks? We examine these risks.
Does topical application of L-carnitine present any risks?
Summary
Published on July 4, 2025, by Jamal, PhD, Doctor of human pathology and infectious diseases — 5 min of reading
Themes:
Why is L-carnitine used in skincare?
In the skincare market, L-carnitine is a preferred ingredient to address lipid metabolism-related skin imbalances. Present in the body, this molecule plays a key role in transporting fatty acids to mitochondria for energy conversion. Applied to the skin, it uses the same mechanism to promote lipid breakdown in subcutaneous tissue, making it valuable in formulations targeting cellulite. The skin benefits of L-carnitine do not end there: studies show it can regulate sebum production, a benefit for oily skin.
Did you know? The carnitine exists in two stereoisomeric forms, D-carnitine and L-carnitine, but only the latter is biologically active.
What precautions should be observed with the topical application of L-carnitine?
To date, L-carnitine is considered a well-tolerated cosmetic ingredient, used in facial treatments for oily or blemish-prone skin. Multiple studies have evaluated this compound at concentrations between 0.5% and 2% without causing adverse skin reactions. L-carnitine is suitable for sensitive skin, with no reports of redness, irritation, or itching after topical application of a product containing this ingredient.
With regard to its use in vulnerable groups such as pregnant or breastfeeding women and young children, available data are limited or lacking. However, the L-carnitine topical form is not considered a hazardous cosmetic ingredient during pregnancy, unlike retinoids or salicylic acid, for example. There are in principle no contraindications for pregnant women to use L-carnitine, although as a precaution it is best to consult their doctor.
This relates to the topical application of L-carnitine, not to its oral administration. Oral intake of L-carnitine during pregnancy should be evaluated on a case-by-case basis with a doctor.
Sources
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DAYANAND C. D. & al. Carnitine: a novel health factor – an overview. International Journal of Pharmaceutical and Biomedical Research (2011).
GROBLER A. F. & al. Topical and transdermal delivery of L-carnitine. Skin Pharmacology and Physiology (2011).
KHAN H. A. & al. A review of the logistic role of L-carnitine in the management of radiation toxicity and radiotherapy side effects. Journal of Applied Toxicology (2011).
EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP). Scientific Opinion on the safety and efficacy of L-carnitine and L-carnitine L-tartrate as feed additives for all animal species based on a dossier submitted by Lonza Benelux BV. EFSA Journal (2012).
PEIRANO R. I. & al. Topically applied L-carnitine effectively reduces sebum secretion in human skin. Journal of Cosmetic Dermatology (2012).
KOETH R. A. & al. Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nature Medicine (2013).
ADEVA-ANDANY M. M. & al. Significance of L-carnitine for human health. IUBMB Life (2017).
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