Timolol dorzolamide

Florez A +,J Am Acad Dermatol 53(5), 909 (with timolol dorzolamide)... 

Timolol-dorzolamide Cosopt Solution Timolol 0.5% Dorzolamide 2% 1 drop twice daily ... 

Percicoi, C. L., Schnell, C. R Dekon, C., and Hariton, C. (1996). Continuous intraocular pressure measurement by telemetry in alpha-chymotrypsin-induced glaucoma model in the rabbit Effects of timolol, dorzolamide. and epinephrine. J. Ocular Pharmacol. 8, 349-358. 

Byeon SH, Kwon OW, Song JH, Kim SE, Park YS. Prolongation of activity of single intravitreal bevacizumab by adjuvant topical aqueous depressant (timolol-dorzolamide). Graefes Arch Clin Exp Ophthalmol 2009 247(1) 35 2. 

A combination product of timolol (0.5%) and dorzolamide (2%) (Cosopt ) is available and can be administered twice daily and provides an additive reduction in IOP. 

Dorzolamide Timolol (Cosopt) [Carbonic Anhydrase Inhibitor/Beta Adrener9ic Bloclcer] Uses Glaucoma Action Carbonic anhydrase inhibitor w/ i-adrenergic blocks Dose 1 gtt in eye(s) bid... 

Opfitfialmic Solution-. 2% dorzolamide hydrochloride and 0.5% timolol maleate (Cosopt). 

Contraindications Bronchial asthma or chronic obstructive pulomonary disease, cardiogenic shock, overt cardiac failure, second and third degree AV block, severe sinus bradycardia, hypersensitivity to dorzolamide, timolol, or any other component of the formulation... 

For topical therapy of open-angle glaucoma, the following groups of drugs can be used for reducing production of aqueous humor, p-blockers (e. g., timolol), a2-agonists (clonidine, brimonidine), and inhibitors of carbonic anhydrase (dorzolamide, brinzola-mide). 

As demonstrated with fluorophotometry, timolol acts predominantly by decreasing the production of aqueous humor and does not significantly alter facility of outflow. Most studies support the view that both short-term and long-term administration of timolol do not alter optic nerve head circulation or produce retrobulbar hemodynamic changes. The ocular hypotensive effect of timolol is additive to most other therapies, including outflow agents (e.g., pilocarpine) and inflow agents (e.g., dorzolamide, brinzolamide, apraclonidine, and brimonidine). When added to latanoprost, timolol and most other P-blockers further reduce lOP approximately 2 mm Hg. This reduction is less than that attained by topical CAIs such as dorzolamide (Table 10-2). 

Brimonidine s efficacy has been compared with that of prostaglandin analogues, topical CAIs, and P-blockers. Results in patients with glaucoma and ocular hypertension indicate that the peak ocnlar hypotensive effect of 0.2% brimonidine is comparable with that of 0.5% timolol (Figure 10-11). When dosed twice daily, 0.2% brimonidine is less effective than latanoprost 0.005% administered once daily. Brimonidine 0.15% with Purite is similar to dorzolamide 2% when used twice daily fc>r treatment of primary open-angle glaucoma or ocular hypertension. 

Dorzolamide -I- timolol Cosopt (Merck) 2% dorzolamide -I- 0.5% timolol solution... 

Monotherapy with three-times-daily 2% dorzolamide and twice-daily timolol 0.5% or betaxolol 0.5% demonstrated peak lOP changes of 23%, 25%, and 21%, respectively. Additive effects on lOP occur when dorzolamide is added to timolol gel solution. 

Dorzolamide was also evaluated in open-angle glaucoma or ocular hypertension patients as monotherapy and when used with timolol and/or pilocarpine for up to 2 years. At 2 years the mean decrease in lOP was approximately 23% for monotherapy patients and 31% to 36% for adjunctive therapy patients. Although dorzolamide was reasonably well tolerated, most patients required adjunctive therapy within 6 months. 

A combination product of timolol 0.5% and dorzolamide 2% is available (Cosopt). This fixed-combination dosed twice daily is equivalent to dorzolamide 2% three times daily and timolol 0.5% twice daily dosed separately. Moreover, the combination product is more convenient, requiring one bottle and fewer drops per day than separate bottles. The combination product used twice daily has been compared with monotherapy with either dorzolamide 2% three times daily or timolol 0.5% twice daily. The mean reduction in lOP was 27.4% (-7.7 mm Hg), 15.5% (-4.6 mm Hg), and 22.2% (-6.4 mm Hg) for the combination product, dorzolamide, and timolol, respectively (Figure 10-16). The dorzolamide-timolol combination was compared with either individual component in patients not controlled on timolol twice daily alone. The combination product was more effective than either timolol 0.5% twice daily or dorzolamide 2% three times daily fitr up to 3 months. The most frequently reported ocular side effect was ocular burning or stinging, with the overall adverse effects being similar for the combination product and dorzolamide, but less for timolol. 

The substitution of brinzolamide for dorzolamide in addition to concomitant administration of timolol demonstrates equivalent lOP reduction but less ocular burning... 

Figure 10-16 Mean intraocular pressure GOP) at hour 2 (morning peak) for dorzolamide, timolol, and the combination product (Cosopt).The combination provided a greater decrease in lOP at all time points than did either single product. (Adapted from Boyle JE, Ghosh K, Gieser DK, et al.A randomized trial comparing the dorzolamide-timolol combination given twice daily to monotherapy with timolol and dorzolamide. Ophthalmology 1998 105 1945-1951.)...

Topical CAls offer distinct advantages over other inhibitors of aqueous humor formation. Compared with P-blockers, CAls reduce the nocturnal aqueous flow rate by 25%. P-Blockers lack the ability to suppress aqueous formation below the already reduced flow rate that occurs during sleep. In contrast to systemic CAls, topical CAls lack most of the systemic side effects while producing a comparable ocular hypotensive effect. None of the topical CAls, however, has the ability to reduce lOP to the level achieved by 500 mg of oral acetazolamide.Topical agents are used in place of systemic CAls for chronic treatment of primary and secondary open-angle glaucomas. Other recently developed medications have probably relegated the position of topical CAls to second- or third-line therapy. Cosopt may simplify therapy and improve compliance for patients who require treatment with both timolol and dorzolamide. 

Adamsons I, CUneschmidt C, PoUs A, et al.The efficacy and safety of dorzolamide as adjunctive therapy to timolol maleate geUan solution in patients with elevated intraocular pressure. J Glaucoma 1998 7 253-260. 

Adamsons lA, PoMs A, Ostrov CS, et al. Two-year safety smdy of dorzolamide as monotherapy and with timolol and pilocarpine.J Glaucoma 1998 7 395-401. 

Boyle )E, Ghosh K, Gieser DK, et al.A randomized trial comparing the dorzolamide-timolol combination given twice daily to monotherapy with timolol and dorzolamide. Ophthalmology 1998 105 1945-1951. 

Fechtner R, McCarroU KA, Lines CR, Adamsons LA. Efficacy of the dorzolamide/timolol fixed combination versus latanoprost in the treatment of ocular hypertension or glaucoma combined analysis of pooled data from two large randomized observer... 

Lass JH, Khosrof SA, Laurence JK, et al. A double-masked, randomized, 1-year smdy comparing the corneal effects of dorzolamide, timolol and betaxolol. Arch Ophthalmol 1998 116 1003-1010. 

Strahlman ER,Tipping R,Vogel R, et al.A double-masked, randomized 1-year smdy comparing dorzolamide (Trusopt), timolol, and betaxolol.Arch Ophthalmol 1995 113 1009-1016. 

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