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