Acute effect of epinephrine on aqueous humor formation in the timolol-treated normal eye as measured by fluorophotometry.
A double-blind, randomized, placebo-control study of the effect of epinephrine on the rate of aqueous formation in eyes pretreated with a beta-adenergic blocking drug was carried out in 25 normal subjects with the use of fluorophotometry. All eyes were pretreated with timolol maleate before epinephrine or placebo was given. The effect of timolol maleate alone was to lower intraocular pressure and to reduce the rate of formation of aqueous humor. In the presence of timolol, aqueous formation was decreased further, approximately 7% more, in the epinephrine treated-eye as compared to the placebo-treated eye. This additional decrease in aqueous formation was statistically significant. No statistically significant difference was found in intraocular pressure or in tonographic C value between the epinephrine-treated and the placebo-treated eye. However, intraocular pressure was so low in both eyes that differences in intraocular pressure were not expected and tonographic tracings were difficult to interpret.
D001082:Aqueous Humor / Q000187:drug effects*; D004311:Double-Blind Method; D004357:Drug Synergism; D004837:Epinephrine / Q000494:pharmacology*; D005452:Fluoresceins; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D010783:Photometry; D011412:Propanolamines / Q000494:pharmacology*; D011897:Random Allocation; D013999:Timolol / Q000494:pharmacology*
D005452:Fluoresceins; D011412:Propanolamines; D013999:Timolol; D004837:Epinephrine