Watch Intently (3)pentobarbital will reduce the extent or result of diazepam intranasal by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Check. Robust or moderate CYP3A4 inducers may maximize amount of diazepam elimination; for that reason, efficacy of diazepam can be lowered.pentobarbital will decrease the extent or impact of