A patient with a documented severe sulfonamide allergy requires a loop diuretic for volume overload. Which loop diuretic is appropriate in this patient?
- A Furosemide
- B Bumetanide
- C Ethacrynic acid ✓
- D Torsemide
Correct answer: C. Ethacrynic acid
Explanation
Furosemide, bumetanide, and torsemide are all sulfonamide derivatives and carry cross-reactivity risk in sulfa-allergic patients. Ethacrynic acid is the only loop diuretic that is not a sulfonamide and can be safely used in patients with sulfonamide allergy. It is reserved for this specific situation due to higher ototoxicity risk. Cross-reactivity between antibiotic and non-antibiotic sulfonamides is debated but ethacrynic acid remains the safest choice.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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