In Brazil, among registered snake bites, those by the genus Crotalus originate the highest mortality rate. The rattlesnake Crotalus durissus terrificus is the most frequently implicated in these accidents. The kidney is a particularly vulnerable organ to the venom of this rattlesnake. In fact, the most serious complication of Crotalus snake bite is the renal dysfunction, and among the fatal cases of Crotalus bites in Brazil 5% are patients treated with antivenom. The hyperuricemia has been observed in human accidents with snake venoms, but this parameter has not received any special attention as a relevant factor in the etiology of renal dysfunction caused by these venoms. This study examined the effects of treatments with low-cost and low-risk uricostatic (allopurinol) and uricosuric (probenecid) drugs on the envenomation by C. d. terrificus, showing that allopurinol and probenecid mitigated certain nephrotoxic effects, as well as the survival of envenomed mice was improved through the effects of allopurinol on reduction of oxidative stress and intracellular formation of uric acid. This new knowledge provides consistent evidences linking uric acid with the renal dysfunction induced by rattlesnake bites and that the allopurinol deserves to be clinically evaluated as an approach complementary to anti-snake venom serotherapy
