Eczema herpeticum, a form of disseminated cutaneous herpes simplex infection, is a potentially life-threatening illness.1 Herpes simplex virus may disseminate either cutaneously or systemically in patients with preexisting cutaneous disease, including Darier's disease, pemphigus vulgaris, ichthyosis vulgaris, mycosis fungoides, and most commonly, atopic dermatitis.1,2 The initial manifest herpes simplex virus infection may be from a primary exposure or after reactivation of a latent infection. The latter infection, occurring in patients with certain preexisting dermatoses, may manifest initially with a localized cluster of lesions which, with time, may disseminate over a larger skin surface area. The manifestation may be confused with an exacerbation of the underlying skin disease until the characteristic vesicles are noted. When associated with atopic dermatitis, the most intense viral dissemination is located in the areas of dermatitis, but normal appearing skin may ultimately be involved. Crops of new vesicles continue to erupt for two to