More and more people are turning to DIY nail solutions to get that fresh-from-the-salon look for less time and money. The latest hack exploding on TikTok is to cure press-on nails with gel polish. The process involves applying gel polish to the underside of a press on in lieu of glue, then curing (aka setting) it with a UV light. It’s the same process that’s used to apply gel extensions, and in theory, allows you to get the longevity of gel tips with the fun and affordable patterns of press-ons. But there’s one problem: While gel tips are clear, most press-ons aren’t. And according to Julie Kandalec, celebrity manicurist and nail educator, in order for gel polish to properly cure, the UV light from the lamp needs to be able to reach the gel, which it can’t do through painted press-ons.

“The nail should be clear or mostly transparent for the light to reach it to be able to cure it. It won’t cure through an opaque nail,” says Kandalec. And when the gel can’t cure, “it will be tacky, not adhere, and can cause an allergic reaction or contact dermatitis.”

Many people are now speaking out on TikTok sharing how they tried this and are now allergic to gel polish.

“I did it,” says Karissa Wampler in a video that now has over 1.5 million views. “My nails looked great until they started itching so bad that I had to literally pour almost boiling water on my fingers just to ease the pain. And then my fingernails were like so squishy underneath they were falling off.”

Contact dermatitis takes time to develop, so while your nails may look and feel great at first, it can take a few days for the allergy to develop.

“Usually with contact dermatitis, it takes several days for the reaction to appear as your body becomes sensitive to an ingredient in the product,” saysPayel Gupta, MD, a board-certified allergist and immunologist for Get Cleared. “That is why sometimes it is difficult to figure out what may be causing the reaction you are having. You may have used the products days before your actual reaction.”

If you do want to gel-cure nails so your nails look longer, seek out clear options. Kandalec likes the Gelish Soft Gel Tips ($30). Once they’re cured onto your nails, you can paint them.

Gelish Soft Gel Tips — $30.00

But if you want to use pre-designed and painted press-ons, gel curing is a no-no. Instead, you can take the steps to make them last nice and long with their intended glue. Wipe your nails with alcohol before applying your press-ons to make sure they have a clean surface to adhere to. And take your time to find the best press-on fit for each of your nails and file them down if needed to get the a perfect fit. “Proper fit is everything—and not just the width, but also the apex or the curve of the natural nail,” explains Kandalec.

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