1. Corneal Edema in Glaucoma Patients After the Addition of Brinzolamide 1% Ophthalmic Suspension
Hisatoshi Tanimura, Atsushi Minamoto, Akito Narai. Jpn J Ophthalmol Vol 49: 327–338, 2005
The afﬁnity of brinzolamide for CA-II is approximately four times that of dorzolamide; therefore, we should consider the potential corneal toxicity of brinzolamide as well as of dorzolamide. In the present cases, it seems most likely that brinzolamide triggered the development of corneal edema. SPK was coincidentally noted in both patients when corneal edema developed. It has been reported that growth inhibition of human corneal epithelial cells by antiglaucoma eyedrops is caused also by the vehicle. Topical brinzolamide suspension contains 0.01% benzalkonium chloride, which is twice as high as that in topical dorzolamide solution. Latanoprost and timolol gel contain benzalkonium chloride with concentrations of 0.02% and 0.005% respectively. Timolol gel 0.5%, which was used in both patients, has also been reported to cause severe corneal damage along with a reduction of tear break-up time. An incompetent epithelial barrier in these patients may have increased the risk of endothelial dysfunction. Brinzolamide 1% was used at a dose of three times daily in the present cases, although its standard dose is twice daily, which thus may have aggravated toxicity.
2. Brinzolamide/Brimonidine: A Review of Its Use in Patients with Open-Angle Glaucoma or Ocular Hypertension
Sarah L. Greig • Emma D. Deeks. Drugs Aging (2015) 32:251–260
Fixed-combination brinzolamide 1 %/brimonidine 0.2 % (Simbrinza®) (hereafter referred to as brinzolamide/brimonidine) is approved for the reduction of elevated IOP in patients with open-angle glaucoma or ocular hypertension in the USA and EU (where treatment is restricted to patients for whom monotherapy provides insufﬁcient IOP reduction), and is the ﬁrst ﬁxed-combination ophthalmic suspension glaucoma therapy available without timolol. This article reviews the pharmacological, therapeutic efﬁcacy and tolerability data relevant to the use of brinzolamide/brimonidine in patients with open-angle glaucoma or ocular hypertension.
A Review of Its Use in the Management of Primary Open-Angle Glaucoma and Ocular Hypertension
Risto S. Cvetkovic and Caroline M. Perry. Drugs Aging 2003; 20 (12): 919-947
Brinzolamide is a nonbacteriostatic sulfonamide derivative with higher lipophilicity and lower aqueous solubility than dorzolamide or acetazolamide at physiological pH. As a consequence, brinzolamide forms a suspension at pH 7.4 which is more comfortable to the eye than the acidic pH of dorzolamide solution (pH 5.6). Brinzolamide is a highly specific, noncompetitive and reversible carbonic anhydrase (CA)-II inhibitor with an ≈4-fold greater in vitro binding affinity for CA-II than dorzolamide. The main local ocular effect of brinzolamide is produced predominantly by inhibition of CA-II in the secretory cells of ciliary processes inside the eye. Inhibition of this isoenzyme reduces the rate of aqueous humour formation, consequently lowering intraocular pressure (IOP). Following topical instillation, brinzolamide enters the blood circulation but systemic adverse effects with its use do not occur mainly because of incomplete saturation and inhibition of CA-II in erythrocytes and kidneys, and the low affinity of brinzolamide for other CA isoforms in the human body.