Physician-reviewed
What is a 503A compounding pharmacy?
Medically reviewed byClay Buchanan, MD·Last reviewed September 2026
A 503A pharmacy prepares patient-specific medications from an individual prescription — for example, a custom dose or a combination not sold commercially. It is a category of pharmacy practice, not an FDA approval, and compounded preparations are not FDA-approved.
How it differs from 503B
A 503B outsourcing facility makes larger batches under different oversight. 503A is patient-specific.
What that means for you
Your treatment plan states whether a medication is commercially manufactured, 503A compounded, or 503B sourced.
Frequently asked
Is compounded lower quality?
It’s different, not lesser — but it isn’t FDA-reviewed, so transparency matters. We name the category on every medication.
References
- FDA: Human Drug Compounding.
This page is for general education. It is not medical advice and does not create a clinician–patient relationship.