Moderate
Suspected
Mô tả
Acyclovir has been associated with reduced phenytoin plasma concentrations in some patients, potentially compromising seizure control during antiviral therapy.
Cơ chế
The precise mechanism is unclear; proposed explanations include increased renal or hepatic clearance of phenytoin, altered protein binding, or impaired absorption during GI side effects of acyclovir.
Ý nghĩa lâm sàng
Case reports document breakthrough seizures with low phenytoin levels during acyclovir treatment; the interaction is not universally observed.
Xử trí
Monitor phenytoin levels during and after acyclovir courses in patients with epilepsy; increase monitoring frequency if seizure threshold changes.