Studi in vitro indicano che irbesartan viene principalmente ossidato tramite il citocromo P450-enzima CYP2C9; l' isoenzima CYP3A4 ha un effetto trascurabile. ###>In vitro studies indicate that irbesartan is primarily oxidised by the cytochrome P450 enzyme CYP2C9; isoenzyme CYP3A4 has negligible effect.