pentobarbital will decrease the extent or influence of mestranol by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Warning/Monitor.pentobarbital will decrease the extent or effect of ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC) by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A4 inducers may