- Salicylic acid is a beta-hydroxy acid most commonly used to unclog pores.
- Salicylic acid can also be beneficial when used on the scalp.
- We spoke with a board-certified dermatologist to break down what you need to know and suggest products.
You may already know of salicylic acid's skin-saving powers: the chemical exfoliant has long been a go-to ingredient in acne product formulas helping to regulate cell turnover and prevent pores from getting overly clogged. What you may not know is that the hero ingredient's benefits are more far-reaching — from head to toe, to be exact. Don't forget, the scalp is also skin, and salicylic acid can be helpful there as well.
What Is Salicylic Acid?
Salicylic acid is classified as a beta-hydroxy acid, or BHA, and can be made synthetically or derived naturally from the bark of a willow tree. "It penetrates into the skin to dissolve dead skin cell buildup, encouraging the top layer of skin to shed," says Dr. Engelman. "Primarily used in skin care to treat acne, salicylic acid has antibacterial, anticomedogenic, and keratolytic — or aiding in shedding dead skin — properties."
What Can Salicylic Acid Do For the Scalp?
Underneath all that gorgeous hair lies the oft-overlooked scalp, which, like skin anywhere else on your body, can experience issues. "Salicylic acid can be a good treatment option for people with scalp conditions such as dandruff and pronounced dermatitis, which can leave your head feeling itchy, dry, and swollen," explains Dr. Engelman. Salicylic acid goes to work just like it would on your face, loosening up dead, flaky skin and oil buildup, which can cause irritation.
What Types of Products Is Salicylic Acid In?
You'll find salicylic acid in everything from shampoos to treatments. A shampoo like Briogeo Scalp Revival ($42) is probably the easiest way to incorporate it into your routine since cleansing your hair requires no extra effort. Even if you don't have a scalp concern, using something like Virtue Exfoliating Scalp Treatment ($48) will help free up follicles from product accumulation and sebum.
A serum like The Inkey List Salicylic Acid Exfoliating Scalp Treatment ($15) that is applied directly to the scalp can help you really hone in on your specific issue and give focused TLC to the area. And because salicylic acid can treat inflammatory conditions like psoriasis and seborrheic dermatitis, know that there are stronger products with a high percentage of salicylic acid that are only available with a prescription, says Dr. Engelman.
Check with your dermatologist if you have a serious issue, and always do a patch test of a new product before applying the full amount.
Are There Any Side Effects to Salicylic Acid?
"Salicylic acid is considered safe for most users, but it can create redness, irritation, or a burning sensation," says Dr. Engelman. She recommends easing into salicylic acid by applying it a few days a week to start and then increasing usage if your skin takes to it well. If your scalp is dry, you may want to use it even less often. And in case you were wondering, there isn't much evidence that salicylic acid can damage hair, she says. "In fact, a healthier scalp can lead to better overall hair health."