Pentobarbital will decrease the level or effect of ketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. pentobarbital decreases levels of elvitegravir/cobicistat/emtricitabine/tenofovir DF by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. May lead to loss of virologic response and possible resistance. pentobarbital... https://bookmarkquotes.com/story20415494/la-guida-pi%C3%B9-grande-per-ordinare-pentobarbital-di-sodio