Good manufacturing practices or GMPs are manufacturing policies and procedures that help ensure the integrity, purity, strength, and consistency of a dietary supplement product. The phrase is not limited to manufacturing activities. Private labelers, distributors, and other companies that hold dietary supplements are also required to comply with US FDA good manufacturing practices.
The requirements for good manufacturing practices vary widely depending on the activities conducted at the particular facility. The following are some of the topics that must be addressed in a company's policies and procedures to ensure compliance:
Personnel qualification & training
Production process controls
Warehousing and distribution controls
Disposal of non-conforming products
Reportable Food Registry
Cleaning of trucks for distribution
There are potentially more policies and procedures that may be required, but whether or not they are necessary is determined on a case-by-case basis and the potential hazards for each type of product.
FDA requires that anyone who manufactures, packages, labels, or holds a dietary supplement, including if you manufacture the supplement but someone else packages or labels the product and if you are the importer. This means that a private labeler would be required to comply with GMP regulations.
The foreign supplier verification program or FSVP also applies to importers of dietary supplements. Dietary supplements are classified as foods under FDA regulations and all foods are subject to FSVP with some exceptions.