All products intended for parenteral administration must be visually inspected for the presence of particulate matter as specified in Injections 1. Dry solids, from which constituted solutions are prepared for injection, meet the requirements for Constituted Solutions in Injections 1 when they are prepared just prior to use. Where used in this chapter, the term essentially free means that when injectable drug products are inspected as described herein, no more than the specified number of units may be observed to contain visible particulates. Particulate matter is defined in Particulate Matter in Injections 788 as extraneous mobile undissolved particles, other than gas bubbles, unintentionally present in solutions. Examples of such particulate matter include, but are not limited to, fibers, glass, metal, elastomeric materials, and precipitates. However, some products, such as those derived from proteins, may contain inherent particles or agglomerates; in such cases, requirements for visible particulates are specified in the individual monograph or in the approved regulatory application.

Where the nature of the contents or the container–closure system permits only limited capability for inspection of the total contents, the 100% inspection of a batch shall be supplemented with the inspection of constituted (e.g., dried) or withdrawn (e.g., dark amber container, suspensions, highly-colored liquids) contents of a sample of containers from the batch. The destructive nature of these tests requires the use of a sample smaller1 than those traditionally used for non-destructive acceptance sampling after 100% inspection. While the tests described in this chapter may be useful during studies to examine product stability, this chapter is not intended to establish any new testing requirements for stability studies.