Generalized pustular psoriasis precipitated by lithium carbonate.

Precipitation of generalized pustular psoriasis was manifested in a patient with previously stable psoriasis vulgaris following lithium carbonate therapy for manic-depressive psychosis. Methotrexate toxicity was observed during the acute stage of the illness, and photochemotherapy was the successful treatment. Further pustulation occurred when lithium carbonate therapy was reintroduced.