The abbreviation USP stands for United StatesPharmacopeia, a document first published in 1820 by theMedical Society of New York State. Recognized as official byCongress in 1848, this document was used as a standardreference by physicians for prescribing medicines. Today, theUSP includes chemical descriptions, identifying tests, andpurity tests, primarily for active ingredients. All materialslisted in the USP are considered drugs by law and subject toall the U.S. Food & Drug Administration requirementspertaining to drugs. Labeling a product or a substance asUSP implies that it conforms to all the legal requirements of the FDA and that it was produced in accordance with theprinciples outlined in FDA’s Good Manufacturing Practices(GMP).
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