FDA reports more adverse-event complaints tied to compounded semaglutide and tirzepatide

The FDA's safety page on unapproved GLP-1 products now lists 990 adverse-event reports associated with compounded semaglutide and more than 730 associated with compounded tirzepatide as of May 31, 2026. Those totals are reports submitted to the agency, not confirmed cases caused by the drugs.

FDA notes that many events reported for compounded products resemble known adverse effects of approved GLP-1 medicines. It also says a report often cannot establish whether the product caused the problem or whether another factor contributed. Because many state-licensed pharmacies are not federally required to send these reports to FDA, the agency says events linked to compounded versions are probably underreported. At the same time, the reporting system cannot be used to calculate how often an event occurs.

The agency lists several separate concerns. Some patients or clinicians have made dosing mistakes with compounded injections. Other products have been prescribed above the dose or faster than the titration schedule in an approved label. FDA has also received complaints about injectable products arriving warm, and it has identified fraudulent labels and products made with semaglutide salt forms that differ from the active ingredient in approved medicines.

FDA is especially direct about retatrutide and cagrilintide. Neither is a component of an FDA-approved drug, and federal law does not allow them to be used in compounding. The agency has also warned companies selling unapproved GLP-1 products directly to consumers under labels such as "for research purposes."

On June 15, 2026, the FDA updated its safety communication on unapproved GLP-1 products used for weight loss. As of May 31, 2026, the agency had received 990 adverse-event reports involving compounded semaglutide and more than 730 involving compounded tirzepatide, and stated plainly that investigational drugs such as retatrutide cannot be legally compounded at all. The update sits inside a broader enforcement arc: about 30 warning letters to telehealth firms in March for misleading compounded-GLP-1 marketing, then the April 30 proposal to remove semaglutide, tirzepatide, and liraglutide from the 503B bulks list. Separately that week, a NEJM Journal Watch summary flagged an elevated rate of suspected drug-induced acute pancreatitis among GLP-1 users compared with sulfonylureas.

Compounded products lack FDA premarket review

A compounded prescription is not reviewed by FDA for safety, effectiveness or manufacturing quality before sale. FDA says compounded drugs should be used only when a patient's medical need cannot be met by an approved product. It advises patients to obtain a prescription from a clinician and fill it through a state-licensed pharmacy.

Anyone using a compounded product should know the exact concentration, dose and source. A patient who receives an injectable product that is warm, poorly packed, mislabeled or different from what was expected should contact the prescriber or pharmacy before using it. Suspected adverse events or quality problems can be reported through FDA MedWatch.

The adverse-event counts are reports, not proven causes, and cannot by themselves prove causation. FDA described concerns including dosing errors, severe gastrointestinal events, and pancreatitis presentations. For anyone still buying compounded GLP-1s from med spas or telehealth sellers, this is the FDA saying the products behind those listings were never approved versions.

Report totals cannot establish event rates

The totals do not show the rate of adverse events, prove causation or permit a safety comparison with an FDA-approved brand. They are not a recall of every compounded semaglutide or tirzepatide product. They also do not mean approved GLP-1 medicines have no risks. Those products have their own prescribing information, contraindications and known adverse effects.

Compounding is not automatically illegal. It can be appropriate under federal and state rules when a patient's needs cannot be met by an available approved medicine. That is different from mass marketing a compounded product as a generic or identical substitute for an FDA-approved drug.

It does not mean FDA-approved Wegovy, Zepbound, or their oral counterparts carry these same risks at these rates; the counts are specific to non-approved products. It is not a recall notice for any one seller. And "cannot be legally compounded" applies to investigational agents like retatrutide specifically, not a new claim about approved drugs.