Purpura after application of EMLA cream in two children.

The eutectic mixture of local anesthetic cream, a 1 : 1 mixture of prilocaine and lidocaine, 2.5% each, is frequently used in pediatric and dermatologic practice to obtain local anesthesia. Side effects include transient skin blanching, erythema, urticaria, allergic contact dermatitis, irritant contact dermatitis, hyperpigmentation, and purpura. We report two children with a purpuric reaction after application of this mixture cream. Purpura after application of this anesthetic cream is a rare nonallergic reaction and only 17 occurrences have been reported, to our knowledge, in the literature. Patch tests could not be performed in our two patients because of lack of parental consent but we suggest that the purpuric reactions were most probably of toxic origin. The pathogenesis of purpura after application of eutectic mixture of local anesthetics cream, which resolves within 2 weeks without dermatologic sequelae and without any specific therapy, is complex. The lesions are probably caused by the direct effect of the cream components on the vessels but many other factors, such as atopic dermatitis, prematurity, subjective predisposition to purpura, trauma, and thrombocytopenia may play important pathogenetic roles.