Can stiripentol reduce fenfluramine use?

Can stiripentol reduce fenfluramine use?

Stiripentol inhibits CYP2C19 and CYP3A4, the enzymes responsible for fenfluramine metabolism. This interaction raises fenfluramine blood levels and prolongs its effect, so many clinicians prescribe lower fenfluramine doses when both drugs are used together.

How does the interaction change dosing recommendations?

The FDA-approved fenfluramine label recommends a 50% dose reduction for patients taking stiripentol concurrently. Without stiripentol, the usual fenfluramine starting dose is 0.2 mg/kg/day, increasing to 0.7 mg/kg/day. With stiripentol, the empiri