Pentobarbital will decrease the level or effect of losartan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown. pentobarbital will decrease the level or effect of vincristine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. pentobarbital will decrease the level or effect of levonorgestrel oral/ethinylestradiol/ferrous bisg... https://livebackpage.com/story5763189/non-ci-sono-altre-pentobarbital-euthanasia-mechanism-of-action-un-mistero