Allopurinol is used as:
a- analgesic agent
b- uricosuric agent
c- antiinflamatory agent
d- antipyretic agent
e- agent which increases renal tubular reabsorption.
Allopurinol inhibits xanthine oxidase, reducing the conversion of hypoxanthine and xanthine to uric acid and resulting in direct inhibition of purine biosynthesis due to elevated oxypurine concentration (negative feedback). Oxypurinol also inhibits xanthine oxidase. So anyway you have dramatically decreased uric acid concentrations, decreased renal tubular transport of uric acid, and then the side effect of increased tubular reabsorption of calcium.
Allopurinol inhibits xanthine oxidase, reducing the conversion of hypoxanthine and xanthine to uric acid and resulting in direct inhibition of purine biosynthesis due to elevated oxypurine concentration (negative feedback). Oxypurinol also inhibits xanthine oxidase. So anyway you have dramatically decreased uric acid concentrations, decreased renal tubular transport of uric acid, and then the side effect of increased tubular reabsorption of calcium.