Prazepam Metabolism after Chronic Administration to Humans

Abstract

1. ¹⁴C-Prazepam (10 mg) was administered to a group of men before and after a course of treatment (10 mg, t.i.d. for one week) with non-radioactive prazepam.

2. Evaluation of the urine collected for seven days after each ¹⁴C-prazepam treatment showed that the multiple dosing did not affect (a) the urinary excretion kinetics of total ¹⁴C, (b) the relative proportions of prazepam metabolites excreted non-conjugated or as glucuronide and sulphate conjugates or (c) the quantities of desalkylprazepam, 3-hydroxyprazepam glucuronide and oxazepam glucuronide excreted in the urine.

3. The major metabolic pathway (prazepam→-3-hydroxyprazepam→oxazepam) proceeded much faster with the 10 mg dose used in this study than it did in an earlier study involving the administration of 25 mg of prazepam.