Samtidig brug af CNS- depressiva, herunder andre opioider, sedativa eller hypnotika, medikamenter til generel anæstesi, fenotiaziner, beroligende midler, skeletmuskel- relaxantia, sederende antihistaminer og alkohol kan medføre yderligere hæmmende virkning.
5 The concomitant use of other central nervous system depressants, including other opioids, sedatives or hypnotics, general anaesthetics, phenothiazines, tranquillisers, skeletal muscle relaxants, sedating antihistamines and alcohol may produce additive depressant effects.