The concomitant usage of METHADOSE with all cytochrome P450 3A4, 2B6, 2C19, 2C9 or 2D6 inhibitors could cause an increase in methadone plasma concentrations, which could result in probably fatal respiratory depression. Furthermore, discontinuation of concomitantly used cytochrome P450 3A4, 2B6, 2C19, or 2C9 inducers could also lead to a rise in met