Tramadol (Contramal Retard 100 mg) and Methadone: interaction and safety
This source-based reference is not a personal treatment recommendation. The relevance and management of an interaction depend on the exact products, route, dose and clinical situation.
Interaction mechanism
Additive central nervous system and respiratory depression; Serotonin-syndrome warning for concomitant serotonergic medicines.
Clinical significance and safety
The listed product includes tramadol; its other opioid component can add to methadone effects, causing marked sedation, low blood pressure and potentially fatal breathing suppression. The methadone label includes this other serotonergic medicine in its serotonergic-drug warning; serotonin syndrome has been reported with such combinations. A prescriber or pharmacist should review the combination; do not independently stop, start or change either medicine.
Using this information
This is a source-based reference record, not a recommendation to combine, stop or change medicines. A missing interaction record does not establish safe use. A qualified healthcare professional should consider the exact products, doses, other medicines and individual health circumstances.