Gentamicin, tobramycin, amikacin, and netilmicin levels in tears following intravenous administration
F. L. Woo, A. P. Johnson, M. S. Insler, W. J. George and W. S. LaCorte
Peak and trough tear and serum concentrations were determined in 27 human
volunteers undergoing intravenous (IV) gentamicin sulfate, tobramycin
sulfate, amikacin sulfate, and netilmicin sulfate therapy. Although
effective serum concentrations were achieved, tear levels were
subtherapeutic. The mean peak tear concentrations were 0.4 microgram/mL,
0.5 microgram/mL, 1.7 micrograms/mL, and 0.3 microgram/mL for gentamicin,
tobramycin, amikacin, and netilmicin, respectively. These levels did not
approach the minimum inhibitory concentrations for Pseudomonas and raise
some concern regarding the risk-benefit ratio of IV antibiotics for
bacterial keratitis.