64-31-3

Processes for reducing the amount of impurities, especially α,β-unsaturated ketones (ABUK), in materials containing morphine. Novel compounds, namely low ABUK morphine sulfate methanolic solvate, and a novel crystal form are also described. The method for making morphine sulfate methanolic solvate comprises mixing a morphine free base composition with methanol to form a solution and adding a liquid comprising sulfuric acid to the solution to form a morphine sulfate methanolic solvate precipitate. A method of making a morphine sulfate compound comprises drying the morphine sulfate methanolic solvate in the presence of water vapor, such that methanol molecules are removed and replaced with water vapor molecules. A composition for treating pain comprises the morphine sulfate compound and at least one pharmaceutically acceptable excipient. A method for treating pain comprises administering to a patient in need thereof the composition comprising the morphine sulfate compound and at least one pharmaceutically acceptable excipient.

In an effervescent formulation containing morphine, inclusion of the morphine in the basic component gives superior storage stability.