butabarbital will lessen the level or effect of zaleplon by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Slight/Significance Not known.butabarbital will lessen the level or impact of pioglitazone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Insignificant/Importance Unidentified.Teniposide: Barbiturates may well lessen the s