Methadone and antiretroviral medications, part I.

The interactions of Methadone with NRTIs and NNRTIs are presented in the first of a two-part article. Methadone is an effective treatment for heroin addiction; however, insufficient information is available on its interactions with HAART. Methadone is metabolized by the cytochrome P450 system, and NRTIs do not appear to be inducers or inhibitors of the cytochrome P450 system. Pharmacokinetics between Methadone and AZT have been studied in detail, and AZT appears to have no effect on plasma Methadone levels. However, NNRTIs do share metabolic pathways with Methadone, indicating that important interactions between Methadone and these drugs are possible, but formal study is still needed. A table of current information is presented on NRTI and NNRTI interactions with Methadone.