Soothing Agents

BHA (Beta Hydroxy Acid)

Reviewed by Daisy · Last updated 14 Aug 2026

Also known as: Salicylic Acid, BHA

Also known as salicylic acid | Best known for exfoliating/anti-acne properties

Addresses

Acne, Blackhead Reducing, Soothing

What Is BHA (Beta Hydroxy Acid)?

BHA is an acronym for beta hydroxy acid, which is more commonly known as salicylic acid. Salicylic acid is a desmolytic ingredient, which means it is able to exfoliate by dissolving the bonds that hold the dead cells to skin's surface. Because salicylic acid is oil soluble, it also has the ability to penetrate into the pore lining and exfoliate inside the pore. This makes it especially effective for reducing breakouts, including blackheads and whiteheads. Salicylic acid is recognized as an over-the-counter topical acne product by the U.S. FDA, when used in concentrations of 0.5-2%.

Even though salicylic acid is best known for its ability to address acne-prone skin concerns, it offers many additional properties that any skin type can benefit from. Case in point, by exfoliating the buildup of dead skin on the surface, it also helps reverse the appearance of dull, uneven skin tone, as well as other visible signs of aging skin. Unlike physical exfoliants (such as a rough facial scrub), salicylic acid offers hydrating properties that enhance the result of smooth, soft skin. Another unique advantage is salicylic acid's ability to gently soothe aggravated skin thanks to its inherent calming properties.

Salicylic acids works most effectively as a leave-on treatment, ideally within a pH range between 3 and 4. Rinse-off salicylic acid cleansers typically have a higher pH, which likely won't offer much of an exfoliation benefit—not to mention the contact time with skin is very brief—but the salicylic acid may at least offer skin-calming benefits in this form and can be included in amounts as low as 0.5% to achieve this benefit. Research shows using salicylic acid starting at a 1-2% concentration is recommended for regular exfoliation within a skin care routine. For more stubborn concerns, higher concentrations can make a dramatic difference.

In dermatologic practices, salicylic acid has been safely used in as high as 50% concentrations for removal of warts, corns, pigmented lesions, and other advanced concerns. Salicylic acid has been found to be safe on all skin tones and ethnicities. Note that BHA is the structural name for salicylic acid and is completely unrelated to the preservative ingredient BHA (butylated hydroxyanisole).

Benefits for Your Skin

How It Works

BHA functions as an antioxidant by donating electrons to free radicals, stabilising them and preventing them from damaging skin cells and other molecules in the formula. This interrupts the chain reaction of oxidative damage that occurs naturally on the skin and within products over time.

Clinical Evidence & References

Published Research

  • Experimental Dermatology, July 2019, pages 786-794
  • European Commission Scientific Committee on Consumer Safety, June 2019, pages 1-70
  • Regulatory Toxicology and Pharmacology, April 2018, pages 245-251
  • Journal of Cosmetic Science, January-February 2017, pages 55-58
  • Clinical, Cosmetic, and Investigational Dermatology, August 2015, pages 455-461
  • Clinical, Cosmetic, and Investigational Dermatology, November 2010, pages 135-142
  • Seminars in Cutaneous Medicine and Surgery, September 2008, pages 170-176
  • Journal of the American Academy of Dermatology, April 2007, pages 651-663
  • International Journal of Cosmetic Science, February 2000, pages 21-52
  • Seminars in Dermatology, December 1990, pages 305-308

How to Use

BHA is typically used as a minor ingredient in formulations rather than as a primary active, so no special application technique is required. It performs its antioxidant function regardless of how the product is applied. If you are using a product containing BHA as one of several ingredients, simply follow the standard usage instructions for that product.

Safety & Precautions

BHA is generally considered safe in skincare products at approved concentrations (typically under 2%). It is not a skin irritant and does not cause sensitivity in most users.

Frequently Asked Questions

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Other forms of BHA (Beta Hydroxy Acid)

These appear on ingredients lists under different names but are the same substance. BHA (Beta Hydroxy Acid) is the common form.

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