Amifampridine Disease Interactions

Amifampridine is contraindicated in patients with a history of seizures. Seizures have been observed in patients without a history of seizures at the recommended doses. Seizures may be dose-dependent. Consider discontinuation or dose-reduction in patients who have a seizure while on treatment.

Amifampridine is extensively metabolized by N-acetyltransferase 2 (NAT2) and hepatic impairment may cause an increase in exposure. The effects of amifampridine have not been studied in patients with hepatic impairment. It is recommended to start treatment with amifampridine in patients with any degree of hepatic impairment at the lowest recommended starting dosage (15 mg/day) and monitor for adverse reactions. Consider dosage modification or discontinuation in patients with hepatic impairment as clinically appropriate.

Renal clearance is an elimination pathway for amifampridine and the inactive metabolite, 3-N-acetyl amifampridine, and exposure of amifampridine is higher in subjects with renal impairment. Patients with renal impairment should be initiated at the lowest recommended starting dosage (15 mg/day), and patients should be closely monitored for adverse reactions. Consider dosage modification or discontinuation in patients with renal impairment as clinically appropriate. Caution is recommended as the safety, efficacy, and pharmacokinetics of amifampridine have not been studied in patients with end-stage renal disease. No dosage recommendation can be made for patients with end-stage renal disease.