Distinguishing Between Compounding Facilities and the Development of the 503B Bulk Drug Substance List

Abstract Due to the 2012 meningitis outbreak linked to compounded steroid injections, the landscape of pharmacy compounding was changed in the United States. This event led to the creation of two distinct types of compounding pharmacies, 503A and 503B facilities. The purpose of this commentary is to describe the differences between 503A and 503B facilities and the policies and restrictions for compounding from bulk drug substances. By doing so, this commentary hopes to bring more attention to the development of the 503B Bulk Drugs List being developed by the Food and Drug Association, and to encourage practitioners and pharmacists to provide insight into the drug substances nominated for the list.