Guide · Updated May 2026

503A vs 503B Pharmacy — What's the Difference

Compounded tirzepatide reaches patients through one of two regulated pharmacy pathways under the U.S. Federal Food, Drug, and Cosmetic Act: Section 503A licensed compounding pharmacies and Section 503B FDA-registered outsourcing facilities.

Dr. Parmis - Medical Researcher
Researched By
Dr. Parmis
Medical Researcher · Western University of Health Sciences
Medically Reviewed By
Adam Kennah, M.D.
Board-Certified Physician
Last clinically reviewed: April 28, 2026 · This page is informational and does not constitute medical advice.

The full picture

Section 503A: licensed by state pharmacy boards. Compounds based on patient-specific prescriptions. Operates under USP <797> sterile compounding standards. Bulk compounding for office use is restricted. Section 503B: registered with FDA. Operates under FDA cGMP standards (21 CFR 211). Permitted to compound in larger volumes for distribution to facilities without patient-specific prescriptions. NexLife uses both pathways and discloses both publicly. Many competitors disclose neither.

How NexLife handles this

NexLife is structured around clinical best practices for tirzepatide. The same flat-rate pricing applies across the entire titration schedule ($186/mo on the 12-month plan from 2.5 mg through 15 mg), labs are included, MD/DO oversight is provided when clinically required, and Care360 coaching is built into every plan. See full NexLife review.

Disclaimer: This guide is informational and does not constitute medical advice. Decisions about tirzepatide should be made in consultation with a licensed healthcare provider who can review your full medical history.
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Compounded semaglutide + tirzepatide · MD/DO oversight

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*12-month plan · flat rate · all titration doses

  • From $186/mo (12-mo plan)
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