Scleroderma and the carcinoid syndrome.

The follow up of a case of the carcinoid syndrome complicated by scleroderma is reported, in which progress of the disease may have been halted by treatment with a combination of cyproheptadine, parachlorophenylalanine and prednisolone. Impairment of tryptophan and 5-hydroxytryptamine (serotonin) metabolism appears central to the development of skin fibrosis in the carcinoid syndrome and may be indicative of important mechanisms in the pathogenesis of idiopathic scleroderma.