USP helps to ensure that consumers receive quality medicines by establishing state-of-the-art standards that pharmaceutical manufacturers must meet. As the world's most highly recognized and technologically advanced pharmacopeia, USP provides standards for more than 3,800 medicines, dietary supplements, and other health care products.

USP Reference Standards are required for use in pharmacopeial assays and tests in the official standards publication, the United States Pharmacopeia-National Formulary (USP-NF). They are selected for their high purity, critical characteristics and suitability for the intended purpose. Unless a USP Reference Standard label states a specific potency or content, the USP Reference Standard is taken as being 100 % pure for the USP purposes for which it is provided.

USP works closely with the Food and Drug Administration (FDA), the pharmaceutical industry, and the health professions, to establish authoritative drug standards. These standards are enforceable by the FDA and the governments of other countries, and are recognized worldwide as the hallmark of quality. USP Reference Standards are established through a process of rigorous testing, evaluation, and quality control. They are independently tested in three or more laboratories - USP, FDA, and academic and industrial laboratories throughout the United States. The Reference Standards are released under the authority of USP's Board of trustees, on the recommendation of the USP Reference Standards Expert Committee, which approves selection and suitability of each lot.

Link to USP web site