High frequency of cough after intravenous bolus injection of Ketogan (ketobemidone + N,N-dimethyl-3,3-diphenyl-1-methylallylamine chloride) for postoperative pain relief.

The frequency of cough 15-45 s after intravenous administration of a low dose of the opioid receptor agonist ketobemidone given for postoperative pain relief was assessed in 121 patients undergoing gynaecological or obstetrical operations. In patients subjected to caesarean section under spinal anaesthesia using bupivacaine, the frequency of an early cough reaction was 50.7%, whereas in patients previously exposed to opioids during the surgical procedure the frequency was 11.1%. This side-effect of ketobemidone has not been reported before.