Acne Information
and Treatment

Salicylic Acid & Acne

Salicylic acid (sometimes referred to as just "SA") is a beta-hydroxy acid naturally present in the bark of the willow tree.[1] However, it is also produced synthetically.[1] While salicylic acid is an "acid," it is a weak acid and is less acidic than the skin is naturally.[3]

Salicylic acid is mainly a keratolytic agent, inhibiting the buildup of keratin cells that can clog pores/sebaceous follicles. It acts by reducing keratin cells' ability to bond together.[1] This effect has been described as dissolving the "intercellular cement" between the keratin cells.[2] While this effect inhibits the buildup of keratin, salicylic acid is not believed to dissolve keratin cells directly, given the inherently tough nature of keratin[2] Instead, it merely detaches keratin cells from the skin.[2]

While salicylic acid has some antimicrobial effects, its antibacterial effects are weak compared to benzoyl peroxide.[7] It's antibacterial effects are mainly "bacteriostatic," meaning salicylic acid negatively impacts the environment for bacteria to grow rather than killing bacteria directly.[8]

However, salicylic acid's main effects remain its keratolytic and comedolytic actions, allowing it to reduce inflammation and the number of comedones(clogged pores), as well as clearing the way for other treatments by penetrating the pores.[4, 8, 9]

When compared to benzoyl peroxide, treatments containing 2.5% benzoyl peroxide and 0.5% salicylic acid have roughly equivalent effects against inflammatory acne, with salicylic acid treatments having fewer negative side effects.[10] However, benzoyl peroxide demonstrates greater effectiveness than salicylic acid against non-inflammatory acne.[10]

Commonly found in acne cleansers, salicylic is deemed safe and effective for the treatment of acne by the United States Food and Drug Administration.[5, 6] In nonprescription acne products, the maximum permitted concentration of salicylic acid is 2 percent.[6]

1. Lin AN, Nakutsui T, Salicylic acid revisited. International Journal of Dermatology. 1998;37:335-42.
2. Davies M, Marks R. Studies on the effect of salicylic acid on normal skin. Br. J. Derm. 1976;95:187-92
3. Mills O, Johnson RW, Adler D, Verdicchio R. Pharmacology of salicylic acid(SA) in acne vulgaris. J. Am Acad Dermatol. Feb.2007.
4. Hashimoto, Y, Suga, Y, Mizuno, Y, Haswgawa, T, Matsuba S, Ikeda S, Monma T, Ueda S. Salicylic Acid Peels in Polyethylene Glycol vehicle for the Treatment of comedogenic Acne in Japanese Patients. Dermatol Surg. 2008;34:276-79.
5. 21 C.F.R. §§ 333.301-333.310 (2007).
6. Akhavan A, Bershad S. Topical Acne Drugs: Review of Clinical Properties, Systemic Exposure, and Safety. Am J Clin Dermatol. 2003;4(7);473-92.
7. Gollnick H, Schramm M. Topical Drug Treatment in Acne. Dermatology. 1998;196:119-125.
8. Gollnick H, Krautheim A. Topical Drug Treatment in Acne:Current Status and Future Aspects. Dermatology. 2003;206:29-36.
9. Taub AF. Procedural Treatments for Acne Vulgaris. Dermatol Surg. 2007;33:1005-26.
10. Christine JC, Arambula K, Chon S, Kimball A. A Double-Blind Comparison of the Efficacy of a Salicylic Acid Based Acne Treatment Versus a Benzoyl Peroxide Based Acne Treatment Regimen for the Treatment of Acne Vulgaris.