pentobarbital raises toxicity of ifosfamide by impacting hepatic/intestinal enzyme CYP3A4 metabolism. Use Warning/Keep track of. CYP3A4 inducers may perhaps increase the metabolism of ifosfamide to its Lively alkylating metabolites.pentobarbital will decrease the level or impact of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism.