butabarbital will reduce the level or impact of zaleplon by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Importance Not known.butabarbital will lower the level or impact of vardenafil by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Watch.Teniposide: Barbiturates may possibly lessen the serum focus of Teniposi