“Conditioned hyperirritability” is a term used to describe the phenomenon wherein a dermatitis on one area of the body results in a heightened irritability of the whole skin, even in areas distant from the initial inflammation. This condition can include a pathologic spectrum ranging in intensity from pruritus to exfoliative dermatitis. Previously this disorder has been known to most dermatologists by other terms, including “autosensitization” and “autoeczematization.” The exact etiology of conditioned hyperirritability, however, remains unknown. It does not appear to be an “id” eruption, as seen in dermatophyte infections, nor has it been found to be secondary to autoantibodies to skin. Conditioned hyperirritability has been associated most commonly with stasis ulcers of the lower extremities, and in some cases allergies to topical medicaments have been found. In this review is presented the clinical entity of conditioned hyperirritability, background research into this phenomenon, and possible etiologic mechanisms involved in conditioned hyperirritability.