An alkaloid obtained from opium by evaporation of the ammoniacal liquid,
after the precipitation of morphine. The residue is added to water,
precipitated by potassium hydrate, and redissolved in ether, from which
codeine crystallizes out on evaporation.
PROPERTIES.--White or nearly translucent, orthorhombic prisms,
octahedral crystals, or a crystalline powder; odorless and having a
faintly bitter taste; slightly efflorescent in warm air. Soluble in
water, alcohol, ether and chloroform.
DOSE.--Dogs, ¹⁄₄ to 1¹⁄₂ gr.