Review of United States requirements for residual moisture in drugs.

Officially recognized procedures for residual moisture determinations on biological products are described. These include gravimetric at ambient temperature and thermogravimetric analysis at specified temperatures for specific products. The bases for selecting the optimum residual moisture for a new product are discussed and values established for currently licensed products are listed. Comparisons are made between the procedures and requirements for biological products and the water determinations specificed in U.S. Pharmacopeia XIX.