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# FDA Adds 4 Bulk Drug Substances to Compounding List
- URL: https://www.fdaweb.com/fda-adds-4-bulk-drug-substances-to-compounding-list/
- Published: 2022-01-27T12:00:00.000Z
- Updated: 2026-09-14T17:30:16.000Z
- Author: David McFarland
- Tags: FDA Policy/General, #legacy-id-D5151024

*Federal Register* notice: FDA has evaluated certain substances that have been nominated for inclusion on a list of bulk drug substances (i.e., active pharmaceutical ingredients) for which there is a clinical need (the 503B Bulks List). Drug products that outsourcing facilities compound using bulk drug substances on the 503B Bulks List can qualify for certain exemptions from the Federal Food, Drug, and Cosmetic Act (FD&C Act) provided certain conditions are met. The agency says it has identified four bulk drug substances that it is including on the list at this time: diphenylcyclopropenone for topical use only, glycolicacid for topical use only in concentrations up to 70%, squaric acid dibutyl ester for topical use only, and trichloroacetic acid (TCA) for topical use only. To view the notice, click [here](https://www.govinfo.gov/content/pkg/FR-2022-01-27/pdf/2022-01558.pdf?ref=fdaweb.com).