Analgesic treatment in acute myocardial infarction. A double-blind comparison of ketobemidone + the spasmolytic A29 (Ketogan) and morphine.

The analgesic effect of ketobemidone hydrochloride + the spasmolytic component A29 (Ketogan) and morphine hydrochloride was compared double-blindly in patients with suspect acute myocardial infarction. The test drugs were administered i.v. in an initial dose of 0.5 ml (2.5 mg Ketogan, 5 mg morphine) followed, if necessary, by additional injections of 0.25 ml. Altogether, 309 patients participated in the trial. The total consumption of the test drugs showed that 5 mg Ketogan was equipotent with 10 mg of morphine. Treatment with Ketogan resulted in a significantly higher proportion of patients who were completely free of pain 15 and 30 min after the initial injection: 16% and 15% more, respectively, compared to morphine. Within 2 hours after the initial injection, approximately 15% of the patients in both treatment groups had reported nausea and about 7% had vomited (patients who vomited or were nauseated before treatment were not included in this analysis). The frequency of other side-effects was low, with no differences between the two treatment groups. Morphine caused a greater reduction of the systolic blood pressure than Ketogan. The effect of both drugs on pulse rate and respiration was the same.