Ototoxicity from lasix

 Q: The risk of ototoxicity from furosemide can be minimized by giving it as a continuous infusion instead of intravenous boluses?

A) True

B) False

Answer: A

 Loop diuretics inhibit the transport in the loop of Henle that is mediated by a Na-K-2Cl cotransporter. An isoform of this cotransporter is present in the inner ear resulting in decreased endolymph secretion and so damage to the inner ear. This manifests as deafness, tinnitus and imbalance. 

Studies have shown that this effect gets highly enhanced with IV boluses of furosemide. Continuous intravenous infusion curtails the risk of ototoxicity remarkably.

#pharmacology

References:

1. Gallagher KL, Jones JK. Furosemide-induced ototoxicity. Ann Intern Med 1979; 91:744. 

2.  Dormans TP, van Meyel JJ, Gerlag PG, et al. Diuretic efficacy of high dose furosemide in severe heart failure: bolus injection versus continuous infusion. J Am Coll Cardiol 1996; 28:376. 

3. Salvador DR, Rey NR, Ramos GC, Punzalan FE. Continuous infusion versus bolus injection of loop diuretics in congestive heart failure. Cochrane Database Syst Rev 2005; :CD003178.