Codeine

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Codeine, alkaloid, C18H21NO3H2O, derivative of opium. It is a white crystalline solid, slightly soluble in water and soluble in organic solvents. When heated, it first loses water and then melts at 157° C (315° F). Chemically a methyl ether of morphine, codeine has similar physiological effects but to a lesser degree, particularly because it is less habit-forming. It is used to reduce pain and to suppress coughing.

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