Interação entre Metadona e Nevirapina

…Methadone Concurrent use of certain protease inhibitors with CYP3A4 inhibitory activity, alone and in combination, such as abacavir, amprenavir, darunavir+ritonavir, efavirenz, nelfinavir, nevirapine, ritonavir, telaprevir, lopinavir+ritonavir, saquinavir+ritonavir, and tipranvir+ritonavir, has resulted in increased clearance or decreased plasma levels of methadone.

…agents (e.g., ketoconazole), protease inhibitors (e.g., ritonavir), fluconazole, fluvoxamine, some selective serotonin reuptake inhibitors (SSRIs) (e.g., sertraline, fluvoxamine) Inducers of CYP3A4, CYP2B6, CYP2C19, or CYP2C9 Clinical Impact: The concomitant use of methadone and CYP3A4, CYP2B6, CYP2C19, or CYP2C9 inducers can decrease the plasma concentration…

Other Agents Analgesics: Methadone ↓ Methadone Methadone levels were decreased; increased dosages may be required to prevent symptoms of opiate withdrawal.

Methadone-maintained patients beginning nevirapine therapy should be monitored for evidence of withdrawal and methadone dose should be adjusted accordingly.

Opiate Agonists: Fentanyl Plasma concentrations may be decreased.

Methadone did not have any effect on nevirapine clearance.