Codeine Alkaloid Crystal

Circa 1920s.

Next to morphine, codeine is the most important of the constituents of opium. These two alkaloids agree in the character but not in the degree of their action. As regards their anodyne and hypnotic properties and their toxic power, codeine has about one fourth the effect of morphine.

In its effects on the nervous system, codeine lessens cerebral activity and the reflexes; causes sleep which, as compared with the sleep due to morphine, is freer from disturbance; is less likely to induce after-headache and nausea; and the various effects on secretion and excretion, so characteristic of morphine, are less pronounced. It is said not to affect the blood pressure, and the pulse remains unaltered, unless the dose is a toxic one. It has, apparently, a selective action on the respiratory apparatus, but it is only by considerable doses that the respiratory movements are retarded. It is supposed to exert a special action on cough through its influence over the pneumogastric nerve. Through the same nerve channel it is probable that codeine is effective in checking that metabolism which results in the production of glycosuria. - The Physiological Action of the Alkaloids of Opium. 2. Codeine

Related Reading:

  • The Discovery of Plant Alkaloids
  • CodeineCrystals