Counterfeit versions of popular weight-loss medications like Ozempic have been appearing in over a dozen countries.

The Partnership for Safe Medicines confirms to NBC News that the counterfeit products have appeared in the United States. So far, there have been no serious side effects from the fake versions. However, the CDC warns that the counterfeit drugs could still be in the supply chain. It is very difficult to spot the fakes, especially if you are accessing the medication through an online pharmacy instead of your health care provider.

Drugs such as Ozempic have been in short supply since March 2022, which has allowed counterfeits to step in and fill the void.