Madelaine Petsch Swears By This $21 Treatment for Keratosis Pilaris

If your idea of a wild Saturday night these days involves lighting some candles and enjoying a little self-care by way of your skin-care routine, you're definitely not the only one. In her latest YouTube video, Madelaine Petsch revealed that she needed a mood-booster after a tough week, so she took fans along for her extensive (and relaxing AF) skin-care regimen.

In the video, the Riverdale star set the scene for her self-care night with one of her favorite candles, the Byredo Scented Candle in Loose Lips (Buy It, $100, amazon.com), gushing that the brand's luxe candles all smell "so incredible."

She then dove into her super extensive skin-care routine, highlighting the many products she relies on to keep her skin looking and feeling soft and smooth. Among her picks were several products by celebrity esthetician Renée Rouleau, including Renée Rouleau Triple Berry Smoothing Peel (Buy It, $89, reneerouleau.com), the Rapid Response Detox Masque (Buy It, $66, reneerouleau.com), the Moisture Infusion Toner (Buy It, $44, reneerouleau.com), and the Skin Recovery Lotion (Buy It, $44, reneerouleau.com).

Petsch also shared her go-to pimple patches, noting she has a few different favorites. One of them is Peter Thomas Roth Acne Clear Invisible Dots (Buy It, $23, amazon.com), which uses salicylic acid to zap zits ASAP. Other times she'll use Skyn Iceland Blemish Dots (Buy It, $22, amazon.com), which treats the skin with both salicylic acid and tea tree oil. Petsch is also a fan of COSRX Acne Pimple Master Patch (Buy It, $12, amazon.com), a waterproof pimple patch that reduces redness and inflammation, and Squish Flower Power Acne Patches (Buy It, $14, anthropologie.com), which deliver pimple-blasting benefits and cover up zits in the cutest way possible. (

But the Riverdale star also revealed that she has keratosis pilaris, a condition that causes the skin to develop red bumps, dry patches, and textures, most commonly on the upper arms and thighs. (More here: What Is Keratosis Pilaris and How Do You Get Rid of It?)

While keratosis pilaris isn't painful or itchy, many people with the condition seek out ways to cover their red bumps and dry patches — including Petsch. "It used to make me incredibly insecure as a kid," she said in her video.

While demonstrating her self-care routine, Petsch said she's been able to reduce the appearance of her keratosis pilaris by using COSRX AHA 7 Whitehead Power Liquid (Buy It, $21, ulta.com). The clarifying treatment helps to decongest pores and keep skin clear with exfoliating alpha hydroxy acids (AHAs). It also uses glycolic acid to reduce the build-up of dead skin cells (which can cause keratosis pilaris), while niacinamide brightens the skin and creates a smoother, softer complexion.

However, Petsch noted that she made a "mistake" when she first started using COSRX AHA 7 Whitehead Power Liquid. Basically, she used too much of the product too quickly, which left her with bright red arms for about a week, she shared in her video.

Orit Markowitz, M.D., associate professor of dermatology at Mount Sinai Medical Center in New York City, says Petsch likely had this initial reaction to the product because of the treatment's "very strong" ingredients, including not just the exfoliating AHAs, but also hyaluronic acid, a humectant (aka moisturizer) that helps draw in moisture from within. When used more than once or twice a week, these types of exfoliating moisturizers can irritate the skin and make keratosis pilaris look more inflamed. In fact, the "how to use" details for Petsch's COSRX AHA 7 Whitehead Power Liquid specifically recommend that the treatment be applied with a cotton pad once a week to start, then you can gradually increase usage to two or three times per week. The product's description also notes that it should not be used in combination with highly concentrated beta hydroxy acids (or BHAs, which tend to be harsher than AHAs), retinol, or vitamin C products, which could all lead to more skin irritation.

Looking for more Madelaine Petsch-approved skin-care tips? Check out the acne spot treatment she uses for "baby soft" skin.