Summary
Administration of thiazide diuretics has been recommended to prevent calcium oxalate urolith development in dogs. To evaluate the effects of thiazide diuretics in dogs, 24-hour urine excretion of calcium was measured in 6 clinically normal Beagles after administration of chlorothiazide (ctz) for 2 weeks, administration of ctz for 10 weeks, and administration of calcium carbonate and ctz for 2 weeks. Compared with baseline values, 24-hour urine calcium excretion did not decrease after ctz administration. When ctz was given at a high dosage (130 mg/ kg of body weight), urinary calcium excretion was significantly (P < 0.04) higher than baseline values. Based on these observations, we do not recommend ctz for treatment or prevention of canine calcium oxalate urolithiasis.
