Guide · Updated 2026-05-08

503A vs 503B Compounding Pharmacies Explained

Plain-language guide to the difference between 503A patient-specific compounding pharmacies and 503B FDA-registered outsourcing facilities.

EducationalUpdated 2026-05-08
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Editorial team
Dr. Sam Saberian · Lead Medical Researcher
Medical review by Alen A. Schwartz, MD · Edited by Julliana Edwards · Last updated 2026-05-11

Overview

Plain-language guide to the difference between 503A patient-specific compounding pharmacies and 503B FDA-registered outsourcing facilities.

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