United States Pharmacopeia (USP)

The United States Pharmacopeia (USP) is a compendium of public quality standards for medicines, pharmaceutical ingredients, excipients and analytical procedures. In laboratory practice, USP standards are used to evaluate requirements related to identity, strength, purity, performance, testing and other quality attributes described in individual monographs and General Chapters.

Pharmacopeial content is published in the USP–NF, which combines the United States Pharmacopeia and the National Formulary. It includes monographs, General Chapters, General Notices, reagents, reference standards and other resources needed to perform and interpret compendial procedures.

How is USP–NF organized?

USP monographs provide specifications and procedures for specific articles, including drug substances, drug products and excipients. General Chapters describe methods, requirements or technical guidance that may apply across multiple products. Proper interpretation therefore requires attention not only to an individual monograph but also to the General Notices and any chapters referenced by that monograph.

Numbers enclosed in angle brackets, such as <71>, <711> and <788>, identify General Chapters. In general, chapters numbered below <1000> contain compendial requirements that may become applicable when referenced, while chapters above <1000> are predominantly informational and provide supporting technical guidance.

USP <71>: Sterility Tests

USP <71> Sterility Tests describes procedures used to test products that are required to meet sterility specifications for the absence of viable microorganisms under the conditions of the test. It is particularly relevant to sterile drug products, parenteral preparations and other articles for which sterility is a defined quality requirement.

USP <85>: Bacterial Endotoxins Test

USP <85> Bacterial Endotoxins Test addresses the detection or quantification of bacterial endotoxins. It is important for products and materials in which endotoxin contamination must be controlled, particularly in parenteral manufacturing and other pharmaceutical applications involving pyrogen risk.

USP <711>: Dissolution

USP <711> Dissolution describes procedures for evaluating drug release from applicable dosage forms under controlled conditions. Dissolution testing is widely used in pharmaceutical development and quality control and can help assess product performance and manufacturing consistency when required by the relevant monograph or specification.

USP <788>: Particulate Matter in Injections

USP <788> Particulate Matter in Injections addresses the evaluation of subvisible particulate matter in injectable preparations. The chapter includes methods based on Light Obscuration and microscopic particle counting, with procedures and criteria that apply according to the preparation and test conditions. It is a key reference for laboratories monitoring particulate contamination in parenteral products.

USP <790>: Visible Particulates in Injections

USP <790> Visible Particulates in Injections addresses inspection for visible particulate matter in injectable drug products. It complements subvisible particle testing by focusing on particles and defects that can be detected visually under defined inspection conditions.

Why is the United States Pharmacopeia important in laboratories?

USP standards provide a common technical framework for analytical development, quality control, method qualification and testing of raw materials and finished products. Correct use of a USP procedure requires more than identifying a chapter number: laboratories need to confirm the current official text, the applicable monograph, the scope of the procedure and whether the requirement applies to the specific article being tested.

It is also important to distinguish harmonization from complete equivalence. Some USP methods are harmonized with corresponding texts in the European Pharmacopoeia and Japanese Pharmacopoeia, but this does not mean that every requirement across the three pharmacopoeias is identical.

Frequently asked questions about the United States Pharmacopeia

Are USP and USP–NF the same thing?

Not exactly. USP refers to the United States Pharmacopeia and is also used for the organization that develops the standards. USP–NF is the publication combining the United States Pharmacopeia and the National Formulary.

What do numbers such as USP <711> and USP <788> mean?

They identify General Chapters. For example, <711> covers dissolution and <788> addresses particulate matter in injections. Applicability depends on the product, its monograph and related compendial requirements.

Can a USP method automatically be applied to any product?

No. The laboratory should confirm the chapter scope, applicable monograph, sample characteristics and relevant regulatory requirements. A compendial method should not be assumed suitable for a different matrix without assessing its applicability.