The Basics
What is Terbinafine?
Used to treat infections caused by fungus that affect the fingernails or toenails.
Brand names for Terbinafine
Lamisil
How Terbinafine is classified
Antifungal Agents
Terbinafine During Pregnancy
Terbinafine pregnancy category
Category BNote that the FDA has deprecated the use of pregnancy categories, so for some medications, this information isn’t available. We still think it’s useful to list historical info, however, given what a common proxy this has been in the past.
What we know about taking Terbinafine while pregnant
There are no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, and because treatment of onychomycosis can be postponed until after pregnancy is completed, it is recommended that Lamisil Tablets not be initiated during pregnancy. Oral reproduction studies have been performed in rabbits and rats at doses up to 300 mg/kg/day [12x to 23x the maximum recommended human dose (MRHD), in rabbits and rats, respectively, based on body surface area (BSA) comparisons] and have revealed no evidence of impaired fertility or harm to the fetus due to terbinafine.
Taking Terbinafine While Breastfeeding
What are recommendations for lactation if you're taking Terbinafine?
Limited information indicates that oral maternal doses of 500 mg daily produce low levels in milk and would not be expected to cause any adverse effects in breastfed infants, especially if the infant is older than 2 months. Monitor the infant for jaundice or other signs of liver toxicity, especially in younger, exclusively breastfed infants. Some sources recommend avoiding oral terbinafine during nursing.[1] Topical terbinafine has not been studied during breastfeeding. Because only about 1% is absorbed after topical application, it is considered a low risk to the nursing infant.[1][2] Avoid application to the nipple area and ensure that the infant’s skin does not come into direct contact with the areas of skin that have been treated. Only water-miscible cream, gel or liquid products should be applied to the breast because ointments may expose the infant to high levels of mineral paraffins via licking.[3]
Maternal / infant drug levels
Limited information indicates that oral maternal doses of 500 mg daily produce low levels in milk and would not be expected to cause any adverse effects in breastfed infants, especially if the infant is older than 2 months. Monitor the infant for jaundice or other signs of liver toxicity, especially in younger, exclusively breastfed infants. Some sources recommend avoiding oral terbinafine during nursing.[1] Topical terbinafine has not been studied during breastfeeding. Because only about 1% is absorbed after topical application, it is considered a low risk to the nursing infant.[1][2] Avoid application to the nipple area and ensure that the infant’s skin does not come into direct contact with the areas of skin that have been treated. Only water-miscible cream, gel or liquid products should be applied to the breast because ointments may expose the infant to high levels of mineral paraffins via licking.[3]
Possible effects of Terbinafine on milk supply
Relevant published information was not found as of the revision date.
Possible alternatives to Terbinafine
(Topical to Toenails) Ciclopirox, Efinaconazole, Tavaborole.
List of References
Lactation sources: Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK501922/1. Butler DC, Heller MM, Murase JE. Safety of dermatologic medications in pregnancy and lactation: Part II Lactation. J Am Acad Dermatol. 2014;70:417.e1-417.e10. PMID: 24528912
2. Leachman SA, Reed BR. The use of dermatologic drugs in pregnancy and lactation. Dermatol Clin. 2006;24:167-97. PMID: 16677965
3. Noti A, Grob K, Biedermann M et al. Exposure of babies to C(15)-C(45) mineral paraffins from human milk and breast salves. Regul Toxicol Pharmacol. 2003;38:317-25. PMID: 14623482
4. Stephen A, Czok R, Male O. Terbinafine: initial clinical results. In, Fromtling RA, ed. Recent trends in the discovery, development and evaluation of antifungal agents. Barcelona: JR Prous Science Publishers, SA. 1987;511-20.
5. Schatz F, Haberl H. Analytical methods for the determination of terbinafine and its metabolites in human plasma, milk and urine. Arzneimittelforschung. 1989;39:527-32. PMID: 2751743
6. Thieme G, Peuckert U. Report on a pharmacokinetic study of SF 86-327 in healthy females in the ablactation period. Sandoz document number 303-019. 1986.
Disclaimer: This material is provided for educational purposes only and is not intended for medical advice, diagnosis, or treatment. Consult your healthcare provider with any questions.
