pentobarbital will lower the level or impact of bexarotene by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Observe.pentobarbital will lower the extent or effect of verapamil by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Warning/Check.And Valeant has long refused to debate such uses of Seconal. As medical su