What is skin slugging, and why is TikTok obsessed with the beauty trend? These are the dos and don'ts of slugging, per dermatologist recommendations.

TikTok has been flooded with the term "slugging" lately – but what could it possibly mean?

Thankfully this viral trend doesn't involve putting any actual slugs on your face, but the slimy creature is something of an inspiration for the fad.

Skin slugging involves sealing your skin with an intensely moisturizing agent like something based in petroleum, generally done overnight.

Most skin sluggers recommend Vaseline, Aquaphor, or CeraVe, and some will do their skincare routines before "sealing it in" with their slugging products.

The order should be serum, moisturizer, and then the petroleum product.

The ultra-hydrating trick can be done anywhere on your body – lips, elbows, legs, feet, wherever there's skin in need of a hydration boost!

As usual in the skincare world, the trend seems to be traced back to K-beauty and its Glass Skin phenomenon, after which slugging content made its way over to TikTok, where it exploded in popularity.

Board-certified dermatologist Dr. Shari Marchbein, M.D., told Teen Vogue that skin doctors have been "slugging" for years. "We just didn't come up with a cute name for it," she said. "I don't go to bed without it!"

While skin slugging can be great for hydration, be careful about slugging if you have oily or acne-prone skin

"If you're trapping things and occluding the skin, there is definitely a potential for breakouts," Dr. Marchbein said, adding that such people can achieve a similar effect to slugging with a creamy moisturizer in place of petroleum.

"Look for ingredients like ceramides, hyaluronic acid, glycerin, and dimethicone. And then you can spot treat with Vaseline where you're drier," she said.

"Selectively slugging" certain dry or eczema-prone spots on your skin can also still work for all skin types – just go easy on the petroleum if you're worried about clogged pores or rashing!