While you may be tempted to skip the pharmacy and just order prescription drugs online, it could be very dangerous to use any unapproved medications from illicit online pharmacies. That’s why the U.S. Food and Drug Administration — along with its international enforcement superfriends — is taking action against hundreds of sites accused of selling prescription drugs illegally online.

The FDA and its friends at Interpol are back with a new round of crackdowns as part of Operation Pangea X. (You may recall the joint task force’s earlier incarnation, Operation Pangea IX, which resulted in the shutdown of thousands of sites selling unapproved drugs and sending them through the mail in 2016.)

As in past years, Operation Pangea was part of the annual International Internet Week of Action, a global cooperative effort aimed at fighting illegal sales and distribution of possibly fake or substandard medical products on the web. This year’s IIWA ran from Sept. 12-19,.

This time around, the FDA says it’s taken action against more than 500 websites accused of illegally selling “potentially dangerous, unapproved versions of prescription medicines, including opioids, antibiotics and injectable epinephrine products to American consumers.”

As part that effort, the agency issued 13 warning letters to the operators of most of the websites targeted in this year’s action.

The warnings instruct companies to ensure that all the products they sell are in compliance with the federal Food, Drug and Cosmetics Act. If they fail to correct any violations, the FDA could take regulatory action against them.

The FDA also worked with domain registrars to seize nearly 100 website domain names, such as buyhydrocodoneonline.com, canadian-pharmacy24x7.com, and buyklonopin.com.

Inspectors working for the FDA — in collaboration with other federal agencies — screened packages suspected of containing illegal drugs at international mail facilities in Chicago, Miami, and New York during the IIWA. As a result, they detained almost 500 packages, which the FDA will check out for possible violations.

“These rogue online pharmacies are often run by sophisticated criminal networks that knowingly and unlawfully distribute illicit drugs, including counterfeit medicines and controlled substances,” said FDA Commissioner Scott Gottlieb. “Consumers go to these websites believing that they are buying safe and effective medications, but they are being deceived and put at risk by individuals who put financial gains above patient safety.”

The FDA warns that buying from fake online pharmacies can be dangerous: You could get counterfeit or substandard drugs, or put your personal and financial information at risk. The agency urges consumers to report any suspected criminal activity to the FDA’s Office of Criminal Investigation.

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