The uric acid test measures levels of uric acid in the blood, which is a waste product from cell breakdown and purine-rich foods. High levels can indicate gout, recurrent kidney stones, or be a side effect of chemotherapy. The test is done via a blood sample and is used to diagnose gout, monitor uric acid levels in cancer patients, and check treatment efficacy for lowering levels. Abnormally high levels signal conditions like gout, while low levels can mean kidney or liver disease.