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§ Regulatory & Safety

Compounding Pharmacy

A pharmacy that creates customized medication formulations, regulated under 503A or 503B rules.

Fact-checked 12 May 2026Plain-English Reference

503A pharmacies make patient-specific compounds based on individual prescriptions; 503B pharmacies ("outsourcing facilities") can produce larger batches under stricter cGMP-like rules. Both are state-licensed; only 503B is registered with the FDA. Quality varies — patients should ask for the pharmacy's name and license number.