When patients ask me about compounded weight loss drugs like semaglutide and tirzepatide, I take a deep breath. The topic is complicated and keeps changing. I won’t just tell patients to avoid them. They’re already looking for these options, and my job is to help them navigate the risks safely.
Dr. Beverly Tchang’s “swim safely” analogy fits well. We can’t stop people from diving into the ocean of compounded products, but we can at least give them floaties: information, caution, and tools to make better decisions. (Tchang, Medscape)
Here’s how I explain it to patients and colleagues, updated with the most recent data.
Why compounded versions exist
When semaglutide and tirzepatide injections were in short supply a few years ago, patients turned to compounding pharmacies that offered custom formulations, often at a lower price. (GoodRx)
In late 2024, the FDA ended the declared shortage of tirzepatide. (Stat News) By early 2025, semaglutide (Ozempic and Wegovy) followed. Once the shortages ended, enforcement ramped up against compounded versions. (GoodRx)
Now, compounded versions are only legal in narrow circumstances, such as when a patient has a medical need that can’t be met by an approved product. (GoodRx)
In December 2024, the FDA sent warning letters to several companies selling unapproved GLP-1 drugs labeled “for research use only.” (Reuters) Some of these contained no active ingredient, incorrect salt forms, or inconsistent potency. (Verywell Health)
Key risks and what to look for
Not all compounding pharmacies operate at the same standard. A friendly local pharmacist doesn’t necessarily mean the product is safe. Dr. Tchang’s checklist gives a good framework for evaluating any compounded GLP-1 medication. A simplified version: look for a pharmacy where the medication is prescribed by a licensed provider, there are no disciplinary actions on file, the pharmacy has been in business for more than a year, only semaglutide base is used (not a salt form), and the facility is FDA-registered or FDA-inspected; it should also be able to ship sterile drugs safely to all 50 states.
If a compounding pharmacy cannot meet these criteria, that’s a red flag. Ask directly for documentation. If they can’t provide it, walk away.
Some compounders also mix in vitamins or preservatives to make their product “different” from the brand name; that may sound harmless, but combining untested additives with peptides can change how the drug behaves. (GoodRx)
A few are promoting oral or sublingual forms of semaglutide and tirzepatide. These seem attractive for patients who don’t like injections, but they haven’t been validated in clinical trials, and absorption is unpredictable. (Omada Health)
Even small changes in formulation or dosing can interrupt treatment and cause rebound weight gain or side effects.
How I approach this with patients
When a patient says, “I found a compounding pharmacy that sells it for half the price,” I acknowledge their concern. Access and cost are real issues. But I explain that the regulatory situation has changed. If an FDA-approved version is available, that’s the standard we should use first.
I encourage patients to ask the pharmacy for their certificate of analysis, sterility test results, and ingredient source; if the pharmacy hesitates or says it’s proprietary, that’s enough reason to stop.
One patient of mine was on a compounded semaglutide microdose that wasn’t commercially available, at least as she described it to me. I never could pin down what she was actually getting. The compounder wouldn’t release potency data either. We moved her to a low-dose commercial version instead. Weight loss slowed a little. Safety and consistency improved, and I knew what was in the pen.
We also reviewed manufacturer assistance programs and insurance coverage. Many patients don’t realize that drug makers often cap out-of-pocket costs for brand medications; cost confusion is one of the biggest drivers behind compounded use.
The FDA’s BeSafeRx campaign
The FDA has an ongoing public safety campaign called BeSafeRx, designed to help patients and providers verify the legitimacy of online pharmacies and compounded drug sources; it offers tools to check pharmacy licenses, identify red flags, and report suspicious products.
It’s a good resource for anyone considering buying compounded or online medications; I often share it directly with patients so they can see what trustworthy sourcing looks like.
You can find the BeSafeRx information at:
What’s changed recently
The REDEFINE trial (NEJM, 2025) studied cagrilintide combined with semaglutide (CagriSema) and showed about 20.4 percent weight loss over 68 weeks, compared with 14.9 percent with semaglutide alone; that kind of data will shape treatment algorithms going forward. GoodRx reports that the FDA’s grace period for compounding GLP-1s has officially ended for both tirzepatide and semaglutide, though some pharmacies still market “custom” or “non-identical” formulations, and regulators are watching closely.
Approach this without judgment if you’re a clinician. Patients are trying to find affordable solutions. And they often trust what they see on social media more than official channels; we can help most by staying informed, asking questions, and documenting carefully. Patients should be cautious for a different reason. Ask your provider to review any compounded medication before you use it, make sure your pharmacy meets every item on that checklist, and use resources like the FDA’s BeSafeRx to verify safety.
Knowledge and transparency remain the best safeguards.
Board Certified in Obesity Medicine and Family Medicine
This blog is for educational purposes only and does not constitute individual medical advice. Always consult your own physician before making changes to your health, medications, or treatment plan.
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