Sorbic acid-induced erythema and edema.

Sorbic acid concentrations as low as 0.1% produced transient erythema with edema and flare after open or closed application to human skin. Multiple areas of the body were tested. Reactions were most intense on the face but also could be produced on the back, forearm, and deltoid areas. Sorbic acid-induced erythema, edema, and flare were not associated with mast cell degranulation. Pretreatment of skin with topical steroids to induce vasoconstriction resulted in a diminished response to sorbic acid. Aspirin blocked the erythematous component, suggesting that prostaglandins are important mediators. Systemic steroids, antihistamines, and hydroxyzine failed to influence sorbic acid-induced erythema and edema. The anti-inflammatory effect of topical steroids was not affected by sorbic acid-induced erythema.