phenobarbital increases toxicity of ifosfamide by influencing hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Keep an eye on. CYP3A4 inducers may well enhance the metabolism of ifosfamide to its Energetic alkylating metabolites.The typical day by day dose with the barbiturate addict is normally about 1.five g. As tolerance to barbiturates