Unauthorized mole and skin tag removers sold on Amazon put the company in the crosshairs of the Food and Drug Administration, which sent a warning letter to the retail giant this month asking that it remove the products from its website.

There are no authorized over-the-counter drugs that remove moles or skin tags, the FDA said in its warning letter, which was addressed to Amazon CEO Andy Jassy. As part of its research, the agency says it bought two of the offending products on Amazon: the “Deisana Skin Tag Remover, Mole Remover and Repair Gel Set” and the “Skincell Mole Skin Tag Corrector Serum.”

The “FDA has safety concerns about drugs marketed OTC directly to consumers for these uses,” the agency said in its letter. Moles should be examined by healthcare providers, the FDA says, and if people try to deal with them at home, there could be delays in cancer diagnoses.

The FDA also issued warning letters to two other companies selling products for removing moles and skin tags on their websites: Ariella Naturals and Justified Laboratories.

Warning letters are the FDA’s initial move against companies that violate US rules around the marketing and selling of unauthorized and unapproved drugs. The companies have 15 days to respond to the letters, which were all dated August 4th, explaining how they plan to address the issue and make sure the products are no longer sold. The agency can take more aggressive actions — like legal injunctions blocking the sale of the products — if the companies don’t comply with the law.

The two mole and skin tag removal products appear to no longer be available on Amazon’s website. But there are still multiple other mole and skin tag removal serums and creams for sale on Amazon, according to a search for “mole remover.”

Amazon has received warnings from the FDA before. In 2021, the FDA sent the company an untitled letter (a step below a warning letter), saying that the sale of sexual enhancement and weight loss products violated the law.