[Skip to Content]
[Skip to Content Landing]
November 1967

Procedure for Evaluating Drug Effects on Increased Intraocular Pressure

Arch Ophthalmol. 1967;78(5):624-628. doi:10.1001/archopht.1967.00980030626013

A procedure is described for evaluating drug effects on increased intraocular pressure (IOP) of the rabbit eye. The elevation of the IOP is obtained by evacuating the anterior chamber of the rabbit eye and replacing the aqueous humor with 0.5% methylcellulose solution in 0.9% saline. The resulting IOP increases steadily over the next two hours from a normal of 20.3 ±1.6 mm Hg to a peak of 29.8 ±1.8 mm Hg as determined in 40 control rabbits. The IOP was measured with a modified Maklahov (Posner-lnglima) applanation tonometer. A dose dependent effect was obtained for the following carbonic anhydrase inhibitors: acetazolamide (regression coefficient [r] = -0.954), methazolamide (r = -0.767), and ethoxzolamide (r = -0.886), when administered orally 30 minutes before the methylcellulose treatment.