dorzolamide and Ocular-Hypotension

To determine whether latanoprost, an ocular hypotensive agent believed to enhance uveoscleral outflow of aqueous humor, augments the aqueous-suppressing effect of dorzolamide, a topical carbonic anhydrase inhibitor.. Twenty-four normal subjects underwent measurement of aqueous humor flow by fluorophotometry to determine the flow with placebo, with dorzolamide, and with a combination of dorzolamide and latanoprost.. The flow of aqueous humor was suppressed 13% by dorzolamide but not by latanoprost. Latanoprost did not augment the effect of dorzolamide on aqueous humor flow; latanoprost and dorzolamide had additive ocular hypotensive effects.. The uveoscleral flow effect of latanoprost does not improve the aqueous-suppressing effect of dorzolamide, but the two drugs have additive ocular hypotensive effects.

Topics: Adult; Aqueous Humor; Carbonic Anhydrase Inhibitors; Double-Blind Method; Drug Synergism; Drug Therapy, Combination; Female; Fluorophotometry; Humans; Intraocular Pressure; Latanoprost; Male; Middle Aged; Ocular Hypotension; Ophthalmic Solutions; Prostaglandins F, Synthetic; Sulfonamides; Thiophenes; Uvea

Hypotony with choroidal detachment is a rare complication of glaucoma medication. In this study, we report on a case which supports the hypothesis that has been proposed to explain this phenomenon.. This study was designed as an observational case report.. A woman with chronic glaucoma underwent trabeculectomy on both eyes. Low intraocular pressure (IOP) developed in 1 eye only, with no visual change for many years. After cataract surgery, the IOP increased, necessitating treatment with topical timolol 0.5% and dorzolamide 2%. She developed monocular hypotony and choroidal detachment 3 months later. This complication occurred in the eye that had previously had a low IOP and resolved completely when topical medication was stopped. The choroidal detachment recurred when rechallenged with the same medication.. Topical aqueous suppression therapy can result in hypotony and choroidal detachment in an eye in which relatively low IOP has been maintained for many years after glaucoma filtration surgery. The problem resolves on stopping the medication.

Topics: Adrenergic beta-Antagonists; Antihypertensive Agents; Carbonic Anhydrase Inhibitors; Cataract Extraction; Choroid Diseases; Chronic Disease; Drug Interactions; Drug Therapy, Combination; Female; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Latanoprost; Middle Aged; Ocular Hypotension; Ophthalmic Solutions; Prostaglandins F, Synthetic; Recurrence; Sulfonamides; Thiophenes; Timolol; Trabeculectomy

Topics: Adrenergic beta-Antagonists; Antihypertensive Agents; Drug Therapy, Combination; Female; Glaucoma, Angle-Closure; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Levobunolol; Macula Lutea; Middle Aged; Ocular Hypotension; Ophthalmic Solutions; Prednisolone; Prodrugs; Pseudophakia; Recurrence; Retinal Diseases; Sulfonamides; Thiophenes; Ultrasonography

Topics: Administration, Topical; Aged; Carbonic Anhydrase Inhibitors; Choroid Diseases; Ciliary Body; Female; Filtering Surgery; Glaucoma; Humans; Intraocular Pressure; Ocular Hypotension; Ophthalmic Solutions; Sulfonamides; Thiophenes; Ultrasonography; Uveal Diseases

L-671,152 is a water-soluble, carbonic anhydrase inhibitor structurally similar to MK-927, a carbonic anhydrase inhibitor that, on topical administration, lowers the intraocular pressure (IOP) of experimental animals and humans. L-671,152 was more potent than MK-927 at inhibiting purified, human erythrocyte carbonic anhydrase II in vitro, as reflected in their respective IC50 values of 0.16 nM and 1.19 nM. Both compounds were compared for topical, ocular hypotensive activity in pigmented rabbits and cynomolgus monkeys. Ocular hypertension was induced in the latter by argon laser photocoagulation of the trabecular meshwork. A 2% solution of L-671,152 was more potent than 2% MK-927 in lowering the IOP of ocular hypertensive monkeys, the maximum reductions being 13.8 mm Hg (37%) and 9.6 mm Hg (27%) at 5 hr and 4 hr, respectively. Moreover, the duration of action of L-671,152 was superior to that of MK-927. The ocular hypotensive effect of L-671,152 was greater than that of MK-927 over a range of concentrations (0.5%-2%) in pigmented rabbits whose IOP was inherently elevated. The peak declines in the IOP of these rabbits after the instillation of 2% solutions of L-671,152 and MK-927 were 6.1 mm Hg and 4.8 mm Hg, respectively. L-671,152 was very effective in lowering the elevated IOP of alpha-chymotrypsinized rabbits and the unilateral instillation of 0.5% L-671,152 into the contralateral eye failed to decrease the elevated IOP of the alpha-chymotrypsinized eye. This finding indicates that the site of action of topically applied L-671,152 is local. The enhancement in the potency of L-671,152 over MK-927 is attributed to a greater inhibition of carbonic anhydrase activity.

Topics: Administration, Topical; Animals; Carbonic Anhydrase Inhibitors; Carbonic Anhydrases; Chymotrypsin; Ciliary Body; Erythrocytes; Female; In Vitro Techniques; Iris; Light Coagulation; Macaca fascicularis; Male; Ocular Hypertension; Ocular Hypotension; Rabbits; Sulfonamides; Thiophenes; Trabeculectomy