The effects of morphine, diacetylmorphine and some related alkaloids upon the alimentary tract: Part II. Small intestine and ileo-colic sphincter

Abstract

1. The effects of morphine upon the small intestine are an increase in the tone and peristaltic movements. The frequency of peristaltic movements is slightly increased at first, but later decreased. The frequency of the rhythmical contractions remains more or less constant while their amplitude is increased. The tone and movements of the ileo-colic sphincter are increased.2. Atropine modifies the effects of morphine by producing a decrease in tone and movements of the intestine, for varying periods of time. The subsequent injection of morphine during the period of inhibition produces, however, a further increase in tone and movements. Adrenalin causes a temporary inhibition of tone and movements after morphine.3. Diacetylmorphine and dihydromorphinone produce similar effects; but are more active than morphine. Dihydromorphinone is approximately 10 times more active, and diacetylmorphine 11/2 times more active than morphine.4. Dihydrocodeinone, codeine and dihydro-oxycodeinone produce similar effects to morphine but are much weaker, especially in so far as the production of increased tone is concerned. Regarding relative activities dihydrocodeinone lies between morphine and codeine, while dihydro-oxycodeinone is placed after codeinone.