A patient who developed exfoliative erythroderma 11 days after the initiation of hydroxychloroquine treatment for psoriatic arthritis is presented. Our experience with her and the continued controversy regarding the incidence of adverse reactions in psoriatic patients to antimalarials prompted a detailed review of the literature. We conclude that the use of antimalarials in patients with psoriasis is associated with a high incidence of severe cutaneous adverse reactions. These medications should not be used in psoriatic patients if other less toxic, effective therapies are available.