Loop diuretics are a mainstay of therapy for many patients with various disorders associated with fluid overload.1 These agents are inexpensive, effective, and well tolerated in the vast majority of patients. The 4 loop diuretics currently on the US market are furosemide, bumetanide, torsemide, and ethacrynic acid.2 Though few comparative studies have been performed, US physicians use the first 3 drugs almost exclusively, reserving ethacrynic acid (due to its ototoxic potential) for patients who have had serious hypersensitivity reactions to
"sulfas" or the other loop diuretics.1,3,4 Ethacrynic acid is the only loop diuretic on the US market that does not contain a sulfonamide substituent. Unfortunately, the sole US producer of ethacrynic acid (Edecrin; Merck & Co, West Point, Pa) is currently unable to provide this drug; in fact, it has stopped production of the oral form indefinitely.5 This can present a dilemma to the clinician who has a patient requiring a loop diuretic who has a history of a serious reaction to a sulfonamide or loop diuretic. We present a case report of such a patient who was successfully treated with a graded-dose challenge to torsemide.