Users of the popular EOS lip balms have launched a class-action lawsuit in the U.S. claiming the colourful products caused their skin to crack, bleed and blister.

According to the lawsuit, several users of the spherical lip balms have experienced “devastating adverse reactions to the product.” Those reactions range from mild rashes, to blistering bleeding and loss of pigmentation that lasted from days to months.

The suit claims that lead plaintiff, Rachael Cronin, found that her lips felt like “sandpaper” hours after using the “Summer Fruit” flavour EOS last month. After she reapplied the balm, her lips began to crack and bleed, leading to a rash that lasted 10 days.

The suit claims that Cronin posted a picture of her lips on Facebook, and received a “frenzy of responses” from others who had experienced the same thing.

“It became clear this was a massive national health problem,” the suit reads.

The lawsuit claims EOS (which stands for “evolution of smooth”) has been informed of the complaints but has failed to place a warning on its products or in any of its advertising.

Cronin has hired well-known California-based lawyer Mark Geragos, who is seeking damages from EOS Products. The suit also asked that the company to “publicly address” the alleged health concerns and issue warnings on its packaging and ads.

EOS responded to the lawsuit Wednesday on its Facebook page, calling it “without merit.” It said in its statement that its products “are safe to use, are made with the highest quality ingredients and they all meet or exceed all safety and quality standards set out by our industry.”