Overview of the Revision to the Guideline 9303 “Guideline for the Establishment of Pigment Detection Methods” in Chinese Pharmacopoeia 2025 Edition

The “Guideline for the Establishment of Pigment Detection Methods” (9303) from the Chinese Pharmacopoeia 2025 edition provides methodological guidance for the detecting both compliant use of pigment as pharmaceutical excipients and potential illegal use. This article comprehensively reviews the classification and nomenclature systems of pigments, introduces domestic and international regulatory frameworks for pharmaceutical pigments, interprets the rationale and specific content of the current revisions, and offers insights and recommendations for further improvements in regulatory oversight and pharmacopoeia compilation.