• The intraocular penetration of tobramycin sulfate, a new aminoglycoside antibiotic, was evaluated in rabbits following subconjunctival injection. The mean tobramycin sulfate concentration in the aqueous humor 60 minutes after a single 5-mg dose was 5.5 μg/ml, as compared to a mean concentration of 6.7 μg/ml following a single 10-mg dose. These levels exceed the minimal inhibitory concentration (MIC) for most Pseudomonas species and a variety of other Gram-negative bacilli recovered from clinical infection. No anterior segment changes that may be attributed to the antibiotic could be demonstrated in the injected eye.
Marwan M. Uwaydah, Bishara M. Faris. Penetration of Tobramycin Sulfate in the Aqueous Humor of the Rabbit. Arch Ophthalmol. 1976;94(7):1173–1174. doi:10.1001/archopht.1976.03910040081015