Unlabelled: Furosemide may trigger life-threatening sulfonamide cross-hypersensitivity reactions, posing a dilemma in patients who need diuretic renal scintigraphy.Methods: We present our experience using ethacrynic acid as a nonsulfonamide alternative diuretic in 5 patients, with a discussion of the diuretic molecular structure, potential side effects, protocol development, and imaging results.Results: Diuretic renal scintigraphy using ethacrynic acid provided useful information about the obstruction status in all patients, with no adverse clinical impact.