The FBI is warning the public about counterfeit compounded weight loss drugs on the market that claim to contain semaglutide, the active ingredient in Ozempic and Wegovy, two prescription medications used for weight loss.

A notice on the FBI’s website warns that the fraudulent drugs purporting to contain semaglutide have been found instead to contain “compounded mixtures of unknown drugs that do not contain semaglutide, drugs with high levels of impurities, and unsafe or unapproved drugs.”

The health risks of taking the “misrepresented drugs” include everything from cardiac and gastrointestinal disorders to nervous system disorders, psychiatric disorders and death, according to the FBI.

The agency warns that the fraudulent drugs are being sold by “noncompliant healthcare providers” including weight loss clinics, pharmacies and medical spas.

In one example, the FBI says a medical spa and weight loss clinic in the South sold its own compounded weight loss medication that was found to contain animal-grade semaglutide with vitamin B12, falling short of regulations set by the U.S Food and Drug Administration.

The FBI says consumers should watch for and avoid “suspiciously low prices” of weight loss drugs sold by unlicensed healthcare providers and should purchase medications only from licensed pharmacies.

The agency also says patients should consult with a medical provider before using any medications for weight loss.

Legitimate versions of compound drugs are copies of FDA-approved medications made by licensed pharmacies and are not approved or inspected by the FDA.

Drug compounding is allowed when drugs are on the FDA’s shortage list, or in circumstances when a patient can’t take a version of a drug made by a pharmaceutical company and need an alternative. Compounded versions of semaglutide require a prescription.

A surge in popularity for medications used for weight loss over the past several years led to shortages of the drugs. The FDA recently declared the shortages “resolved,” removing drugs including Ozempic and Wegovy from its shortage list.

The FDA subsequently announced a timeline for when most compounded versions may no longer be made.

State-licensed pharmacies must stop making most compounded semaglutide (copies of Novo Nordisk’s Wegovy and Ozempic) by April 22, and larger outsourcing pharmacies by May 22, pending any court rulings.

Ozempic is approved by the FDA to treat Type 2 diabetes, but some doctors prescribe the medication “off-label” for weight loss, as is permissible by the FDA.

Wegovy contains the same main ingredient as Ozempic, semaglutide, and is FDA-approved for weight loss in people with obesity or who are overweight with at least one weight-related condition. It is also approved to reduce the risk of major cardiovascular events in adults with obesity or who are overweight with established cardiovascular disease.

Semaglutide works by slowing down movement of food through the stomach and curbing appetite, thereby causing weight loss.