What is salicylic acid? - Salicylic acid is an organic acid that has been used for many years in the topical treatment of psoriasis. Salicylic acid is used as a keratolytic agent. Its keratolytic effect occurs by dissolving the intracellular matrix and softening of the stratum corneum, the upper skin layer .
This promotes the shedding of psoriatic scales and reduces the scale build-up and softens the plaques . This effect is achieved in concentrations up to 6% whereas higher concentrations are destructive to the tissue .
+ Can be used to limit scale build-up and softening of plaques
+ Used for many years as a topical treatment for psoriasis
- Topical salicylic acid decreases the efficacy of UVB phototherapy.
- Because of greater risk of toxicity, salicylic acid should not be used for children .
What does science say?
Data on salicylic acid used alone on psoriatic plaques is limited. However, because of the keratolytic effect, salicylic acid is sometimes used as an adjunctive treatment that is believed to enhance the penetration of topical therapeutics .
For instance, a combination treatment including salicylic acid with a corticosteroid was shown to be more effective than the corticosteroid treatment alone, in people with moderate plaque psoriasis following a 3-week study period .