Renal Neomycin Excretion in the Dog

This study examines the mechanism (s) of renal neomycin excretion in dogs. Neomycin is approximately 40% bound to serum protein and the mean neomycin fractional excretion is 68%. Since (a) the sum of protein binding and the fractional excretion of neomycin approximates 100%, (b) the low molecular weight of neomycin should facilitate its filtration, and (c) other aminoglycosides like gentamicin which are not bound to protein have not been shown to be absorbed or secreted by renal tubules, it appears likely that glomerular filtration is the main mechanism responsible for neomycin excretion by the kidney. The authors express their sincere appreciation for the excellent technical contribution of Miss Bonnie Keith.