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Glossary 

# BHA (Beta Hydroxy Acid)

BAY-tuh hy-DROK-see AS-id 

## Definition

Beta hydroxy acid refers primarily to salicylic acid, an oil-soluble exfoliant that penetrates into pores to dissolve excess sebum and dead skin cell buildup. Unlike AHAs, which work on the skin's surface, BHAs can reach inside the pore lining, making them particularly effective for acne-prone and oily skin types. Salicylic acid also has anti-inflammatory properties, which help calm redness and irritation associated with breakouts. BHAs are commonly found in cleansers, toners, spot treatments, and leave-on exfoliants at concentrations of 0.5% to 2%. They are generally well-tolerated but can cause dryness if overused. BHAs are also used in higher concentrations in professional chemical peels for deeper exfoliation and pore-clearing effects.

## Related Terms

[Salicylic Acid](/glossary/salicylic-acid)[Chemical Exfoliant](/glossary/chemical-exfoliant)[Comedone](/glossary/comedone)[Sebum](/glossary/sebum)

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