Is GreenwichRx legit?

GreenwichRx is a 503A compounding pharmacy based in Tomball, TX. It operates under state board of pharmacy licensure. We are not aware of any recent public FDA enforcement actions against the pharmacy, though compounding pharmacy regulatory history can change. Always verify current status with your state board of pharmacy.

Where is GreenwichRx located?

GreenwichRx is headquartered in Tomball, TX. The pharmacy is licensed to ship to 0 US states.

What does GreenwichRx produce?

GreenwichRx produces compounded semaglutide and compounded tirzepatide in addition to other compounded preparations. As a 503A pharmacy, it dispenses compounded medications in response to individual patient prescriptions under state board of pharmacy oversight.

What is the difference between 503A and 503B?

503A pharmacies prepare compounded medications for individual patients in response to specific prescriptions and are regulated primarily by state boards of pharmacy under USP sterile compounding standards. 503B outsourcing facilities register directly with the FDA, follow current Good Manufacturing Practices (cGMP), and can produce compounded medications in larger batches without patient-specific prescriptions. 503B facilities are subject to FDA inspection.

Compounding Pharmacy · Tomball, TX · 503A

GreenwichRx Review

GreenwichRx (Greenwich Rx) is a 503A sterile compounding pharmacy in Tomball, Texas that compounds patient-specific semaglutide and tirzepatide (GLP-1) for weight loss. It complies with USP chapters 795, 797, and 800, partners with the Professional Compounding Centers of America (PCCA) for premium-grade ingredients, and maintains state licensure across the U.S. Note: routine 503A compounding of GLP-1s that copy commercially available products is restricted now that the FDA shortages are resolved.

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503APCCA

Location: Tomball, TX

Phone: 844-202-4446

Website: greenwichrx.net

States licensed: 0

6.0

★★★☆☆3/5

Editorial score · methodology

Telehealth Providers Sourcing From This Pharmacy

These telehealth brands are reported to fulfill some or all compounded GLP-1 prescriptions through GreenwichRx. Sourcing arrangements can change over time.

7.9/ 10

Verified partner

Trimi Health

Best for: budget-conscious shoppers

★★★★☆4/5

Editorial score · methodology

$99/mo

CompoundedSemaglutideTirzepatide

Get Started Read full Trimi Health review →

7.2/ 10

Good Girl Rx

Best for: patients seeking multiple compounded GLP-1 formats with pharmacy quality standards

★★★★☆3.6/5

Editorial score · methodology

$79/mo

CompoundedSemaglutideTirzepatideOzempicWegovyLegitScript Verified

Get Started Read full Good Girl Rx review →

Certifications & Compliance

All sterile compounding pharmacies in the United States are required to follow United States Pharmacopeia General Chapter <797> sterile compounding standards^[4], with finished preparations evaluated against USP <71> sterility testing^[5] and USP <85> bacterial endotoxin testing^[6] as appropriate for the product type.

PCCA

Professional Compounding Centers of America — membership network supplying compounding pharmacies with pharmaceutical-grade ingredients, formulations, and training.

Drugs Produced

Compounding pharmacies' ability to produce semaglutide or tirzepatide depends on the FDA Drug Shortage List status for each reference product; compounding eligibility can change when a drug moves on or off the shortage list^[7].

Semaglutide

Compounded semaglutide produced

Tirzepatide

Compounded tirzepatide produced

States Licensed

GreenwichRx has not published a state-by-state licensure list. Verify licensure for your state directly with your state board of pharmacy before filling a prescription here.

Regulatory Actions

No public FDA enforcement actions or recalls are on file in our records for GreenwichRx. Regulatory status can change — verify with the FDA and your state board of pharmacy before relying on this information.

Weight Loss Rankings Score Breakdown

Accreditation & Compliance6/10

Regulatory Standing9/10

State Coverage0/10

GLP-1 Production10/10

Track Record5/10

Scores are independently researched. See our methodology for details.

Medium confidence · Last verified 2026-06-04 via manual · How we verify provider data

Frequently Asked Questions

Key terms, explained

New to GLP-1s? Tap any term for a quick, plain-English definition.

Semaglutide · Drugs and brands
Tirzepatide · Drugs and brands
Compounded GLP-1 · Pharmacy and drug forms
503A pharmacy · Pharmacy and drug forms
503B outsourcing facility · Pharmacy and drug forms
PCAB accreditation · Pharmacy and drug forms
Off-label use · Insurance and regulatory
FDA Drug Shortage List · Insurance and regulatory

See Top Semaglutide Providers All Pharmacies

Sources & methodology — as of July 2026

1.FDA — Compounding and the 503A Pharmacy Framework— U.S. Food & Drug Administration.
2.FDA — 503B Outsourcing Facility Registration and Requirements— U.S. Food & Drug Administration.
3.PCAB — Pharmacy Compounding Accreditation Board Standards— Accreditation Commission for Health Care (ACHC) / PCAB.
4.USP General Chapter <797> — Pharmaceutical Compounding: Sterile Preparations— United States Pharmacopeia.
5.USP General Chapter <71> — Sterility Tests— United States Pharmacopeia.
6.USP General Chapter <85> — Bacterial Endotoxins Test— United States Pharmacopeia.
7.FDA — Drug Shortages Database (current shortage listings)— U.S. Food & Drug Administration.