ABSTRACT
International harmonization is a complex process as indicated by the failure of previous attempts (before 1989) at world harmonization of pharmacopeial standards. The pharmacopeial text, test methods, purity specifications, and limits for the impurities are not only scientific and technical, but also are legally binding. Pharmacopeias differ in procedures and policies that make harmonization efforts more difficult. Harmonization of excipients is complicated because large numbers of excipients are not a single chemical entity but are rather complex mixtures of similar chemical compounds. Many are derived from natural sources and some are synthetic polymers. They are produced by many suppliers, and many manufacturing methods are used in their production. These substances are also used in the food industry, chemical industry, cosmetic industry, and agriculture. The pharmaceutical use of many excipients is only a small part of the total business.
