Dermatopharmacology of Salicylic Acid

Abstract

The acute contra-inflammatory effects of salicylic acid, three standard dermatocorticoids and four contact antiphlogistics have been investigated by means of a UV dermatitis inhibition test in the guinea pig. The substances tested had a distinct inhibitory effect on the development of erythema and can be ranked in the following ascending order of activity (percent of maximum possible score): bufexamac = 36%, salicylic acid = 37%, hydrocortisone = 44%, acetylsalicylic acid = 48%, flumethasone pivalate = 51%, fluocinolone acetonide = 52%, phenylbutazone = 56%, and indomethacin = 58%.

The role of salicylic acid in the treatment of psoriasis

“…In 1885 large‐scale production of synthetic salicylic acid began. It is one of the oldest known keratolytics 7 and a well‐established treatment for many dermatologic conditions, including psoriasis 46 …”

“…1). Dermatotherapeutic effects occur only with topical application of the free acid; the esters and salts are more effective as percutaneous or internal agents 7 . It can be used in almost any vehicle in concentrations of 0.5–60%.…”

“…Salicylic acid can be photoprotective, and also has bacteriostatic and bacteriocidal activity against yeast and Gram‐negative and Gram‐positive bacteria 6 , 7 …”

“…In concentrations ≥ 0.1%, salicylic acid exerts a photoprotective action. In concentrations of 5% and above, it exerts an increasingly potent and rapid deep keratolytic effect on the stratum corneum and ultimately an exfoliative action 7 . Concentrations of up to 50% salicylic acid in plaster are currently used to remove warts, corns, and calluses.…”

“…6 Today there are many therapies for psoriasis, all with varying degrees of effectiveness and safety. Salicylic acid is one commonly used topical agent; 6 however, although salicylic acid has been known for more than a century, 7 there is a remarkable lack of published data on its use in psoriasis.…”