Salicylic acid is a popular skincare ingredient that helps clear pores and fight acne, but it can harm your skin’s protective barrier if you use too much of it.
Your skin has a natural barrier, like an invisible shield on the surface. This barrier, called the stratum corneum, locks in moisture and keeps out germs, irritants, and dryness. It is made of dead skin cells held together by lipids, proteins, and ceramides. When the barrier works well, your skin stays hydrated, balanced in pH, and protected from infections.[2][3][6]
Salicylic acid comes from willow bark and belongs to a group called beta hydroxy acids, or BHAs. Unlike other exfoliants that only work on the surface, salicylic acid is oil-soluble. This means it slips deep into pores filled with oil and debris. It breaks the bonds between dead skin cells, dissolves excess sebum, and clears clogs that lead to blackheads and pimples. It also calms swelling and controls oil production over time.[2][4][7]
This deep action makes salicylic acid great for oily or acne-prone skin. It exfoliates gently inside pores without scrubbing, reduces bacteria-friendly environments, and prevents new breakouts.[4][8]
The problem starts with overuse. Salicylic acid disrupts the “glue” between skin cells, including healthy ones in the barrier. When you apply it too often, especially at high strengths or combined with other exfoliants like AHAs, it increases water loss from the skin. This is called transepidermal water loss, or TEWL. Studies show that using 2% salicylic acid twice daily with glycolic acid raised TEWL by 39% in weeks, leading to dehydration and hidden inflammation before you see redness.[2]
Overdoing it strips natural oils and proteins, thinning the barrier. Your skin gets dry, sensitive, and irritated. It might overproduce oil to compensate, worsening clogs. The barrier’s pH shifts, upsetting good bacteria and inviting infections. In extreme cases, like on warts, too much can cause burns, blisters, or long-term sensitivity.[3][5][6]
Signs of barrier damage include tightness, flakiness, stinging from products, and more breakouts. Even moisturizers after application cannot fully stop the damage, as they repair but do not block the acid’s effects.[2]
To use salicylic acid safely, start low, like 1-2% strength, once or twice a week. Build up slowly based on how your skin reacts. Pair it with hydrating, barrier-supporting ingredients like ceramides. Avoid mixing with strong actives daily. If damage appears, pause and focus on gentle repair.[2][3]
Sources
https://www.oreateai.com/blog/scientific-methods-for-removing-fat-granules-around-the-eyes-a-professional-guide-from-dermatologists/1322244e182499d79e5ddd1f11b9b6ae
https://www.alibaba.com/product-insights/is-using-two-exfoliants-daily-aha-bha-causing-my-barrier-damage-or-just-myth.html
https://worldofasaya.com/blogs/acne/healing-acne-damaged-skin-barrier-repair-guide
https://flychem.com/blogs/articles/how-to-use-a-salicylic-acid-cream-safely-benefits-strengths-mistakes-to-avoid
https://int.livhospital.com/amazing-what-happens-if-you-use-too-much-salicylic-acid-on-a-wart/
https://www.kins-clinic.com/blogs/how-to-close-pores-permanently-the-truth-about-what-really-works
https://www.healthgennie.com/blog/salicylic-acid-vs-glycolic-acid
https://theordinary.com/en-us/blog/understanding-spot-solutions.html
