[Prevention of urinary calculi by means of a benzbromarone-citrate combination]

The action of a benzbromarone citrate combination (Harolan) in the prevention of uric acid and oxalate stones was studied in 21 patients suffering from calcium oxalate stones. The investigation was carried out under standard diet to eliminate possible variabilities in the excretion of lithogenous and inhibitory substances due to individual eating habits. Under Harolan a significant reduction in the serum uric acid level as well as simultaneous elevation of the urine pH-value could be achieved, the latter resulting in improved solubility of uric acid, the excretion of which is increased during the first days of treatment. Neither in 24 hour urine nor in the circadian rhythm was the solubility curve for uric acid exceeded during the test period. Side-effects were not observed.