Effect of a new analeptic drug, almitrine, on fentanyl-induced respiratory depression and analgesia in man.

Five female patients received fentanyl 0.0066 mg kg-1 i.v. (group A); five other female patients received the same dose of fentanyl, followed immediately by almitrine 0.5 mg kg-1 i.v. (group B) and 20 minor gynaecological operations were performed under a combination of almitrine 0.5 mg kg-1 and fentanyl 0.0066 mg kg-1 (group C). In group A, fentanyl produced a marked and significant respiratory depression (P less than 0.001). In group B and C, almitrine antagonized the fentanyl-induced respiratory depression. Analgesia did not seem to be affected.