The Food and Drug Administration is alerting Americans to the potential dangers of at-home COVID-19 tests after receiving reports of people egregiously misusing them, resulting in injuries.

In a safety communication released Friday, the FDA said it had received reports of injuries after people used the kits’ liquid test solution as eye drops or stuck the solution up their noses. “The liquid test solution is not supposed to touch your body,” the FDA wrote sternly. The agency also reported that some children had been injured after putting test components in their mouths and swallowing the solution.

“The liquid solutions may include chemical ingredients, such as sodium azide, that help the test work properly or act as preservatives,” the FDA wrote. “The test chemicals can be irritating or toxic if they get on your skin, nose, or eyes or if they are swallowed.”

At-home tests all have slightly different protocols, but they often involve combining a test solution and nasal swab samplings on a test card. In Abbott’s popular BinaxNow test, for example, people are instructed to put six drops of a test solution onto a testing card. Then test-takers swab their noses, insert the swab into the primed test card, seal the card, and wait 15 minutes for results. In the iHealth COVID-19 test, test-takers swab their noses, swirl the swab in a test solution, then squeeze three drops of the solution onto a test card and wait for results.

According to the FDA, some people have put the test solution onto the swab before swabbing their nose, resulting in the test solution being swirled around their nostrils.

It’s unclear how many people have been injured by these testing snafus or how serious their injuries were. However, the FDA would like you to stop it. The agency recommends that everyone keep their test kits out of reach of pets and small children. Once you’re ready to use your kit, read the directions and follow them. The agency also helpfully recommends that you “keep the liquid solution away from the skin, nose, mouth, and eyes. Do not swallow the liquid solution,” and “use only the swab in the test kit to collect a nasal sample.”

“FDA authorized at-home COVID-19 tests have become an important and convenient tool that people can use to check if they or a family member are currently infected with SARS-CoV-2, the virus that causes COVID-19,” the regulator notes. They’re also perfectly safe to use—when you follow the directions.