The serum uric acid lowering effects of 100 mg Allopurinol (A), 20 mg Benzbromarone (B) and the combination of both were tested in a randomized block-trial in 12 male patients suffering from hyperuricemia and hyperlipoproteinemia type IIb/IV. Therapy periods lasted 4 weeks each. Allopurinol lowered the uric acid concentrations from 7,54 mg/100 ml to 5,95 mg/100 ml, Benzbromarone from 7,54 mg/100 ml to 6,11 mg/100 ml and the combination from 7,54 mg/100 ml to 4,90 mg/100 ml, all three significantly. The difference between the effect of the combination drug and Allopurinol and Benzbromarone respectively was also significant. An additive effect of both components is evident. Serum creatinin concentration remained constant. Uric acid and creatinin excretion could not be evaluated because of failure of patient compliance in the collecting of urine.