[Possibilities and limitations of eye drops for glaucoma therapy].

backgroundIn Germany, chronic open-angle glaucoma is mostly treated by daily eye drop application. The possibilities and limitations of this form of therapy are presented. Reasons for the change in the selection of the preferred substances over time are also discussed and the limits of local drug therapy are described.

objectivesWhat effects can be expected of the available drugs? MATERIALS AND

methodsThe article provides a review of the literature from PubMed and clinical experience.

resultsIn chronic open-angle glaucoma, eye drops containing a single agent can achieve an intraocular pressure decrease of 15-35 % compared to the initial pressure level. This is dependent on the substance and is achievable when used as directed. Difficulties in administration are often observed in older patients where regular use over extended periods of time is required. In addition, there are limits in the achievable pressure reduction by combining several active ingredients. Novel systems are being developed for future applications. The idea is to achieve a continuous slow release of the active substance by surgical application of a biodegradable carrier.

conclusionA treatment regimen which is individually tailored to the individual patient's needs should be developed by the attending physician and the achievement of the set objectives should be monitored at regular intervals. However, restrictions induced by patients due to inadequate adherence or by the drug due to limited efficacy of the drug have to be considered. Therefore, eye drop therapy in open-angle glaucoma is not always sufficient. It should be supplemented in due time by laser or filtering surgery before the affected patients and their optic nerves suffer advanced glaucomatous damage.