terbinafine, Lamisil, Lamisil AT (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

SIDE EFFECTS: The most common side effects of terbinafine are:

Oral terbinafine can cause liver failure sometimes leading to liver transplantation or death.

PRESCRIPTION: Yes (Tablets), OTC (Topical preparations)


PREPARATIONS: Tablets: 250 mg. Oral Granule: 125 and 187.5 mg. Cream, Gel, solution, or spray: 1%.

STORAGE: All formulations should be stored at room temperature, 15 C - 30 C (59 F - 86 F).


  • Tablets: The usual dose is 250 mg once daily for 6 weeks for treatment of the fingernails, and 12 weeks for treatment of toenails. Optimal results will not be seen for several months after treatment because it takes time for new healthy nails to grow. Terbinafine may be taken with or without food.
  • Cream, gel, spray, solution: Apply to affected area (s) once (jock itch, ringworm) or twice daily (athletes foot) for about for 1 week.

DRUG INTERACTIONS: Rifampin reduces oral terbinafine blood concentrations, potentially reducing the efficacy of terbinafine. Cimetidine (Tagamet) may increase oral terbinafine blood levels, potentially increasing side effects of terbinafine. Fluconazole (Diflucan) increases the blood levels of oral terbinafine by 52%-69%. Potentially leading to increased side effects.

PREGNANCY: There are no adequate studies in pregnant women. Since nail fungus treatment can be delayed until after pregnancy there is no reason to use oral terbinafine during pregnancy.

NURSING MOTHERS: Breastfeeding mothers should not use oral terbinafine because terbinafine passes into breast milk.

Medically reviewed by Eni Williams, PharmD

Reference: FDA Prescribing Information

Medically Reviewed by a Doctor on 9/14/2015

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Pill Finder Tool

Need help identifying pills and medications?
Use the pill identifier tool on RxList.

Back to Medications Index