Studie in vitro ukazují, že irbesartan je primárně oxidován cytochromem P 450, a to enzymem CYP2C9; izoenzym CYP3A4 má zanedbatelný význam.
In vitro studies indicate that irbesartan is primarily oxidised by the cytochrome P450 enzyme CYP2C9; isoenzyme CYP3A4 has negligible effect.