[Preservatives in ophthalmic formulations: an overview]

Effect of Long-Term Topical Antiglaucoma Medication Use on the Ocular Surface

Purpose:

The purpose of this study was to describe the prevalence and pattern of ocular surface disease (OSD) in glaucoma patients using preserved topical antiglaucoma medications in a Nigerian population.

Methodology:

A comparative study of patients who had used topical preserved antiglaucoma medications for 6 months or more with age- and sex-matched individuals who were not on any other form of topical eye medication was carried out using fluorescein tear breakup time (FTBUT), Schirmer I test, and ocular surface staining with fluorescein and lissamine green. The right eyes of 103 eligible patients with primary open-angle glaucoma and that of 103 age- and sex-matched individuals (controls) were included in the study.

Results:

The prevalence of OSD among users of preserved topical antiglaucoma medications was significantly higher than among nonusers as assessed by FTBUT (83.5% vs. 57.3%;P < 0.001), Schirmer I (30.1% vs. 17.5%; P = 0.033), and ocular surface staining (62.1% vs. 31.1%;P < 0.001). Users of preserved topical antiglaucoma medications also had worse grades of OSD evaluated by FTBUT (P = 0.001), Schirmer I (P = 0.023), and ocular surface staining (P < 0.001).

Conclusion:

The prevalence of subjective OSD was significantly higher among users of topical antiglaucoma medications than nonusers. Hence, preserved topical medication use is a serious concern for increased ocular surface morbidity among glaucoma patients. This calls for more attention to be paid to the consequences of OSD among glaucoma patients on topical medications.

Dry Eye Disease: Consideration for Women's Health

Dry eye disease (DED) is a multifactorial disorder of the ocular surface and tear homeostasis that can result in discomfort, pain, and visual disturbance. Untreated, DED can become chronic, progressive, and significantly affect an individual's quality of life. Women are disproportionately affected by DED, are diagnosed at a younger age, and experience more severe symptoms compared with men. DED is associated with a wide range of comorbid conditions; there is a strong association between DED and autoimmune disorders, especially those that affect women at many times the rate of men. Treatment response questionnaires indicate women respond better to a wellness model of treatment for DED than men. Furthermore, women's health care-seeking behaviors provide opportunities for general practitioners, specialists, and women's health centers to help identify women with DED or at risk for DED for referral to an eye care specialist. This review of the prevalence of DED in women, and gender and sex-specific aspects of DED, highlight a significant opportunity for action. Earlier diagnosis and treatment of this common but burdensome condition could significantly improve a woman's quality of life.

Preservative toxicity in glaucoma medication: clinical evaluation of benzalkonium chloride-free 0.5% timolol eye drops

Timolol (generic name) is a frequently used medication for the control of glaucoma. Benzalkonium chloride (BAK) is a commonly used preservative in ophthalmic solutions with a broad range of antimicrobial activity; however, this nonspecificity can result in toxicity. Adverse effects attributed to BAK, including conjunctival inflammation and fibrosis, tear film instability, corneal cytotoxicity, anterior chamber inflammation, trabecular meshwork cell apoptosis, cataract development, macular edema, and even systemic effects, have been well documented. These effects can lead to ocular discomfort, poor intraocular pressure control, glaucoma surgery failure, and decreased patient compliance. BAK use in topical medications has decreased recently as newer and less toxic preservatives have become available. Yet these preservatives still exert some toxic effects, especially in patients with chronic eye disease who use multiple drops over extended periods of time. Thus, attempts to reduce overall preservative loads for patients are important, whether it be decreasing the amount of preservative, decreasing the total number of drops patients use, or eliminating preservatives entirely. A preservative-free formulation of timolol, TIMOPTIC® in OCUDOSE®, is available in unit-dose vials. Preservative-free unit-dose vials minimize toxic adverse effects and are a good option for patients with ocular surface disease, on long-term multidrop therapy, or who simply do not tolerate the effects of preservatives due to discomfort.