Contraindicated (1)pentobarbital decreases amounts of vandetanib by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Keep away from coadministration with potent CYP3A4 inducers; these drugs lower exposure to vandetanib by up to forty%.pentobarbital will reduce the level or impact of fosaprepitant by influencing hepatic/intest