The principal cytochrome P450 isoenzyme included appears to become CYP2E1, with CYP1A2 and CYP3A4 as supplemental pathways. About 85% of an oral dose appears during the urine within 24 hrs of administration, most given that the glucuronide conjugate, with modest amounts of other conjugates and unchanged drug (see OVERDOSAGE) for toxicity informatio