Introduction

The main aim of treatment in glaucoma is to reduce intraocular pressure. Good evidence from multiple large randomised trials shows that reducing intraocular pressure is effective in preventing disease progression in ocular hypertension, primary open angle glaucoma, and even in so called normal tension glaucoma. Target pressures in the low teens are associated with the lowest progression rates.

Medical treatment

βblockers

blockers—for example, timolol, carteolol, betaxolol levobunolol, and metipranolol—reduce the secretion of aqueous and are the most commonly prescribed topical treatment. Contraindications to their use include a history of lung or heart disease, as the drops may cause systemic β blockade. Topical β blockers can unmask latent and previously undiagnosed chronic obstructive pulmonary disease in elderly people.

Systemic effects from eye drops can be reduced by occlusion of the punctum (finger pressed on the caruncle, which is felt as a lump at the inner canthus of the eye) or shutting the eyes for several minutes after putting in the drops. This reduces the lacrimal pumping mechanism and stops the drops running down the lacrimal passages and being absorbed systemically through the nasal mucosa or by inhalation directly into the lungs. It may also enhance ocular absorption of the drugs. Drops are usually given twice a day, but long acting forms can be given once a day, either alone or in combination with other drops.

Eye closure to reduce systemic side effects after instilling drops