(The Hill) — Many online pharmacies that are selling semaglutide, the main ingredient in weight loss drugs such as Ozempic and Wegovy, are doing so illegally, according to new research.

The study, released Friday in the journal JAMA Network Open, found that when researchers used search engines to try and find “websites advertising semaglutide without a prescription” in the summer of last year, 42.27 percent of the online pharmacies that came up “belonged to illegal pharmacy operations.”

“This qualitative study found that semaglutide products are actively being sold without prescription by illegal online pharmacies, with vendors shipping unregistered and falsified products,” the study reads. “Two websites evaluated were sent [Food and Drug Administration (FDA)] warning letters for unlawful sale of unapproved and misbranded semaglutide.”

Tim Mackey, an author of the report and professor at the University of California, San Diego, said those who are shopping online for the anti-obesity meds are facing “serious consumer risks” of receiving medicine that is fake, ineffective and potentially dangerous.

The research echoes alerts from the World Health Organization (WHO), which warned in June that fake versions of semaglutide were located, and being sold, in different countries.

The World Health Organization (WHO) put out a medical product alert in June that warned of fake versions of semaglutide, diabetes drug, being located in different countries

“WHO advises healthcare professionals, regulatory authorities and the public [to] be aware of these falsified batches of medicines,” Dr. Yukiko Nakatani, WHO assistant director-general for Access to Medicines and Health Products, said in a statement. “We call on stakeholders to stop any usage of suspicious medicines and report to relevant authorities.”

Manufacturers have found it difficult to keep up with the demand for the anti-obesity meds, which can cost up to $1,300 per month, the study found. Because of this, the number of people searching for the medicine on online pharmacies has increased, exacerbating the rise in “knock off” products, per the research.

Mackey added that the rise in potentially illegal online sales can also be credited to insurance plans that do not cover the injections or patients whose doctors will not write them a prescription for the drug. Medicare also will not pay for the medicine when they are prescribed for weight loss, the study explained.

Mackey and his colleagues tested six different samples of semaglutide from different online pharmacies. In their study, they found that at least two of the pharmacies had received warning letters from the Food and Drug administration for the unlawful sale of misbranded semaglutide.

The drugs purchased online also contained up to 39 percent more semaglutide than was labeled on the medicine, the research found. Overdosing on the medicine could lead to nausea, vomiting and dangerous drops in blood sugar, which can make people feel sick, per the FDA.

Pharmaceutical company Eli Lilly announced in June that it was filing several legal actions against med-spas, wellness centers and other entities that used unapproved products resembling their weight loss drug.