4-Hydroxypyrazolo (3,4-d) Pyrimidine (HPP) in the Treatment of Gout: Preliminary Observations

Abstract

From a study of 4 patients with gout it is confirmed that the xanthine oxidase inhibitor 4-hydroxypyrazolo (3,4-d) pyrimidine (HPP) effectively lowers the serum uric acid level. The urinary concentration of uric acid also falls and that of xanthine and hypoxan-thine rises. There appears to be a slight fall in overall purine excretion. 300 mg. HPP daily has been shown to be an adequate maintenance dose in these patients. Two of the patients developed a rash during this therapy. This may have been due to the drug, but further experience indicates that the complication is not so common as these figures suggest. One patient experienced 2 acute attacks of gout during the first 3 weeks of therapy. It is believed that this was the result of lowering the serum uric acid rather than of the HPP itself. Concomitant colchicine treatment is therefore advisable when starting the drug.