What condition are children on chemotherapy likely taking zyloprim (allopurinol) to prevent?

Zyloprim, or allopurinol, is commonly prescribed for children undergoing chemotherapy to prevent the formation of uric acid crystals, which can lead to kidney stones. Chemotherapy can increase cell turnover, resulting in the release of purines that break down to uric acid. This elevated level of uric acid can contribute to a condition known as tumor lysis syndrome, where the rapid destruction of tumor cells leads to metabolic disturbances, including hyperuricemia.

By administering allopurinol, the production of uric acid is inhibited, helping to maintain lower levels in the bloodstream and consequently reducing the risk of kidney stones, which can be a serious complication. This preventive measure is crucial for managing the side effects associated with chemotherapy. The other options presented do not relate directly to the primary use of allopurinol in this context.