Pentobarbital will reduce the extent or effect of tamoxifen by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Check. pentobarbital will lower the extent or result of saxagliptin by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Small/Importance Unknown. pentobarbital will decrease the level or result of ketoconazole by impacting hepatic/intestinal enzym... https://citychemiststore.com/product/buy-nembutal-powder-online/