THE EFFECTS OF MORPHINE AND ITS DERIVATIVES ON INTESTINAL MOVEMENTS 2. THE EFFECT OF MORPHINE ON THE PRESSURES DEVELOPED BY THE INTESTINAL MUSCULATURE

¹ From the Laboratory of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan

The injection of morphine subcutaneously is followed by an increase in magnitude of movement, of pressures developed, and of the work done by the intestinal muscle of an ileal loop in the dog.

These results lead to the further tentative conclusion that morphine increases the oxygen consumption of smooth muscle. The high pressures developed after morphine may be a factor in the constipating effect of this drug.

It is suggested that clinicians should determine whether such high pressures in the intestinal lumen develop in the case of man after the use of morphine and whether or not these pressures, if occurring, would be deleterious for cases involving weakened or distended portions of the gastro-intestinal tract.