[Additive therapy with carboanhydrase inhibitors for open angle glaucoma previously treated with timolol 0.5% drops]

Inhibitors of carboanhydrase (ICA) in the form of dorzolamide 2% drops and brinzolamide 1% drops are in use for 8-10 years, with a significant intraocular pressure (IOP) lowering effect. The goal of the present study was to obtain precise data on the efficacy of local ICA in conjunction with timolol 0.5% drops, and to evaluate the incidence of side effects. This was a prospective study that lasted 2 years and included 110 patients. Initial IOP values, before therapy with ICA, amounted to 19 +/- 8.4 mm Hg in group A and 20.5 +/- mm Hg in group B. Although the results obtained demonstrated statistically significant lowering of IOP (in group A by 4.5 +/- 2.4 mm Hg, and in group B by 4.6 +/- 2.1 mm Hg) after therapy with ICA, the difference between the groups was not found. Dorzolamide more frequently caused local side effects like aching, itching and pain in the eye. Aditional lowering of lOP in our patients was somewhat greater than reported before (4.6:4.3). Side effects (itching, aching, pain) were three times more frequent in the group treated with dorzolamide than reported by other authors; this difference could be due to patient age, as our patients were mostly elderly people and the data are subjective. The results of this study suggested the effectiveness of additional local therapy with ICA in patients with open angle glaucoma.