To the Editor.—
A letter to the editor in the December 1978 issue of The Lancet initiated a discussion of the usefulness of cimetidine therapy in patients with psoriasis or psoriatic arthritis.1 Regarding the efficacy of this therapeutic approach, a number of rather contradictory results were published, describing both beneficial and neutral effects on skin and/or joint lesions.2-5 Our observation of a single patient with psoriatic arthritis in whom the eruptions disappeared while he was receiving cimetidine therapy prompted us to study ten additional patients with this disease.Short-term cimetidine therapy (14 to 28 days) was started at a dosage of 1 g/day, with a reduction to 600 mg/day after two weeks. Eight of the patients suffering from both psoriasis and psoriatic arthritis were at the same time being treated with nonsteroidal anti-inflammatory drugs. In two psoriasis patients without arthritis, all oral as well as topical treatment was