Studies of drugs given before anaesthesia. XII. A comparison of papaveretum and morphine.

Papaveretum 20 mg and morphine 10-20 mg, with and without the addition of hyoscine, were compared as pre-operative medication, studying also the operative and postopsrative sequelae. It is shown that the morphine content of papaveretum 20 mg is equivalent to 13.3 mg of morphine sulphate and this dose was included in the comparison. Papaveretum caused a higher incidence of pre-operative drowsiness than the corresponding dose of morphine but the latter was more effective in relieving apprehension. There was no important difference in the toxic effects of the drugs during the first 90 minutes. There was less operative hypotension after papaveretum 20 mg than after any dose of morphine used but papaveretum-hyoscine had the highest incidence. Nausea and vomiting after papaveretum 20 mg were more frequent than after morphine 10 mg but similar in incidence to the sequelae of morphine 15 mg. In a small group of patients, papaverine in a dose many times greater than that found in papaveretum, behaves similarly to an inert substance with regard to both desired and toxic effects. The question of the potentiation of morphine by the other alkaloids included in papaveretum is discussed in general terms.