The principal cytochrome P450 isoenzyme concerned seems to get CYP2E1, with CYP1A2 and CYP3A4 as more pathways. Somewhere around 85% of the oral dose appears during the urine inside 24 hrs of administration, most because the glucuronide conjugate, with little amounts of other conjugates and unchanged drug (see OVERDOSAGE) for toxicity information.W