BHA means beta hydroxy acid. These acids dissolve in oil and help remove dead skin and sebum, the oil inside pores. That makes salicylic acid useful for congestion rather than simply adding moisture. Dryness alone is not a reason to add an exfoliant, however persuasive the word "glow" looks on a shopping page. Too much exfoliation can remove structures that hold water and healthy fats in the skin.4

How should you introduce it on dry skin?

  1. 1Test a small amount on one or two small areas you want to treat for three days. Continue only if there is no reaction or discomfort.
  2. 2Wash gently with a mild cleanser and your fingertips. Avoid scrubbing tools or abrasive cleansers.
  3. 3Apply following your bottle's directions, using it less often initially. Treat the affected area rather than automatically applying it everywhere. Keep it away from your eyes, mouth and inside your nose.
  4. 4Keep moisturizer in your routine, morning and night. Choose a noncomedogenic moisturizer, meaning one formulated not to clog pores.
  5. 5Use SPF 30 or higher sunscreen every day. When outdoors, choose broad spectrum, water resistant protection.
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Increase frequency only after your skin has adjusted, without exceeding your bottle's instructions. If dryness or irritation develops, use it less often. Neither morning nor evening needs to become a compulsory exfoliation slot: the priority is tolerating the product and following its directions.2

Paula's Choice 2% BHA Liquid for sensitive skin

Dry, sensitive skin needs particular caution with exfoliation. Do not apply salicylic acid to broken, red, swollen, irritated or infected skin. Avoid adding scrubs, other exfoliating products or drying cosmetics to the same area. If you use benzoyl peroxide, a topical retinoid such as tretinoin, or another medicated skin product, ask your doctor before combining them with salicylic acid.23

Discuss use with your doctor if you are pregnant, trying to become pregnant or breastfeeding. Seek medical advice for severe or persistent irritation or stinging. Stop using salicylic acid and get emergency help for difficulty breathing, throat tightness, faintness or swelling of the face, lips or tongue.2

Paula's Choice 2% BHA Liquid for sebaceous filaments

Sebaceous filaments are normal structures that move oil to the skin's surface, not acne plugs. They usually look smaller, flatter and lighter than blackheads. Salicylic acid can help make them less noticeable, but they cannot be permanently removed, which is an awkward detail for anything marketed as a pore eraser. Avoid squeezing them or removing them with pore strips: removing filaments can dry out skin, and squeezed pores refill.7

Paula's Choice 2% BHA Liquid for blackheads on the nose

Salicylic acid helps break down blackheads and prevent clogged follicles. If your nose has blackheads but your cheeks are dry and clear, target the affected area rather than treating your whole face. Give a tolerated acne treatment six to eight weeks before adding another. General acne treatment timelines put fewer breakouts at four to eight weeks; they are not a specific timetable for this liquid.123

Paula's Choice 2% BHA Liquid for closed comedones

Closed comedones are whiteheads: plugged follicles covered by skin, often appearing as small flesh colored bumps. Salicylic acid is one treatment option. Comedonal acne can take eight to twelve weeks to start improving and many months to clear. Do not pick or squeeze the bumps. See a dermatologist if treatment is not helping, or if you develop deep, painful spots or scarring.16

Where this answer comes from

  1. 1Adult acne treatment dermatologists recommendaad.org
  2. 2Salicylic Acid Topical: MedlinePlus Drug Informationmedlineplus.gov
  3. 3Salicylic aciddermnetnz.org
  4. 4Facial Acids: Everything You Need To Knowhealth.clevelandclinic.org
  5. 5Acne: Tips for managingaad.org
  6. 6Comedonal Acne: Causes & Treatmentmy.clevelandclinic.org
  7. 7Sebaceous Filaments: Difference From Blackheads & Treatmentmy.clevelandclinic.org