Most healthy children can take terbinafine safely, but baseline assessment reduces rare hepatotoxicity events.
Absolute: hypersensitivity to terbinafine, chronic or active liver disease. Relative: renal impairment, CYP2D6 substrate co-therapy, psoriasis/lupus flare history, pregnancy.
History of hypersensitivity to terbinafine or any formulation components
Active or chronic liver disease with significant hepatic impairment
Baseline hepatic dysfunction or elevated transaminases—obtain labs before therapy and monitor every 4–6 weeks during prolonged courses
Chronic kidney disease with creatinine clearance <50 mL/min
Concomitant CYP2D6 substrates with narrow therapeutic index (tricyclic antidepressants, some beta-blockers)—consider dose adjustments
Psoriasis or systemic lupus erythematosus—rare flares reported; monitor skin changes
Pregnancy or lactation—limited pediatric data; weigh benefits vs risks