Terbinafine topical has been assigned to pregnancy category B by the FDA. Animal studies using high oral and subcutaneous doses have not revealed evidence of teratogenicity. There are no controlled data in human pregnancy. Terbinafine should only be used during pregnancy when the need has been clearly established.

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Terbinafine is excreted into human milk in small amounts. Following a 500 mg oral dose of terbinafine to two subjects, 0.65 mg and 0.15 mg were excreted into breast milk, representing 0.13% and 0.03%, respectively. Excretion of terbinafine into breast milk following topical exposure is expected to be minimal. The manufacturer recommends that due to the potential for adverse reactions in nursing infants, a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother. Nursing mothers should avoid applying terbinafine topical to the breast.

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