Treatment of polycythemia vera with hydroxyurea.

Thirty-six patients with polycythemia vera were treated with hydroxyurea for 12 to 67 months. Nineteen patients were previously treated with other drugs. In the vast majority of patients, an average dose of 1 g/day was sufficient to control hematocrit value and platelet count. Half of the patients experienced relief of pruritus, and two thirds experienced regression of splenomegaly. None of the patients had either thrombotic complications or leukemia. Four patients suffered from mild side effects, which included fever, hyperbilirubinemia, and stomatitis, and were relieved of their symptoms when treatment was stopped. However, two patients experienced renal failure, a possible major complication not described previously.