What is the best option for glaucoma

Medical therapy

The aim of any glaucoma therapy is to preserve the optic nerve and thus the visual field and to prevent the disease from progressing. As a rule, glaucoma is first treated with medication. Many patients can be helped with it. But if the intraocular pressure with medication - and in our case that means: with eye drops - is not reduced sufficiently, the drops are not tolerated or the application is difficult, there are good alternatives such as laser and surgical methods.

In the vast majority of cases, drug therapy is a lifelong measure. Systemic therapy, i.e. taking tablets, is only indicated in exceptional cases, e.g. in the case of an acute glaucoma attack, for a short-term lowering of intraocular pressure.

Drug glaucoma therapy lowers intraocular pressure, which - as described - is an important risk factor for glaucoma if it is higher than the pressure tolerance of the individual optic nerve corresponds to.

With all available drugs, further progression of the disease should be prevented. When choosing the appropriate drug, the doctor will depend on the individual effectiveness and the side effects and contraindications of the individual drug groups. With all glaucoma drugs, allergies and intolerances must also be expected. These are usually not caused by the drug itself, but by preservatives - the fact that many highly effective drugs such as prostaglandins are now available in preservative-free form has considerably increased the safety and comfort for the patients.

Your ophthalmologist will decide which eye drops to lower intraocular pressure are right for you on the basis of your findings and after weighing the benefits and risks, and will make you a corresponding recommendation in the doctor-patient consultation.

The most important drug classes are presented below - without an assessment being possible at this point. Because only one person judges the success of a therapy: the patient, whose eyesight can be secured and kept stable despite glaucoma.

Prostaglandins

Prostaglandins were introduced in the mid-1990s and have quickly become the most important class of antiglaucomatous drugs in developed countries. Since these substances work even in very small amounts, it is often sufficient to drip them once a day.

Prostaglandins work by using a drainage path for the aqueous humor (the uveo-scleral drainage) that is otherwise hardly used by nature. This can effectively lower the intraocular pressure. Eye reddening may occur during prostaglandin therapy. In some cases, the iris can become permanently discolored. Another unusual side effect observed by some patients is increased eyelash growth. The main active ingredients are latanoprost, travoprost and bimatoprost.

Beta blockers

Beta blockers in the form of eye drops were introduced into our glaucoma therapy in 1978. The first substance and the most frequently prescribed was timolol, followed later by the active substances propanolol, betaxolol, levobunolol, metipranolol, carteolol, pindolol and befunolol, which also belong to this class. The beta blockers quickly gained a reputation for being the “gold standard” in glaucoma therapy, and they are still a very important treatment option today. An undeniable advantage: after more than a quarter of a century of use and in view of the millions of pressure-regulated patients with them on five continents, doctors and patients alike have an immense wealth of experience and can assess and weigh up their benefits and risks very well.

If the doctor does not find any contraindications such as asthma, low blood pressure or certain heart diseases, there are few concerns about its use. They have to be dripped once or twice a day and generally cause few problems locally. Beta blockers lower the intraocular pressure by reducing the production of aqueous humor.

Carbonic anhydrase inhibitors

The local carbonic anhydrase inhibitors dorzolamide and brinzolamide inhibit the enzyme carbonic anhydrase, which regulates aqueous humor production. There is evidence that these substances can also directly improve blood flow to the optic nerve and retina. This would be a great advantage for all patients who also suffer from blood flow-related risk factors such as migraines, too low or too high blood pressure, cold hands or feet. Short-term conjunctival irritation can occur locally after the instillation and occasionally a metallic taste in the mouth. Local carbonic anhydrase inhibitors are used three times a day in monotherapy and twice a day in combination with beta blockers.

Alpha agonists

Brimonidine is another innovative glaucoma drug, it probably works on a combination principle by reducing the production of aqueous humor and having a positive influence on its outflow. The results of animal experiments also suggest a neuroprotective effect. Side effects can include lowering blood pressure, tiredness and dry mouth. Older preparations are clonidine and apraclonidine. In contrast to these, brimonidine has fewer side effects, as it acts much more specifically on a certain type of alpha receptors (alpha-2 selectivity).

Other antiglaucoma

The classic of glaucoma therapy is pilocarpine - it was introduced at the time of the blessed Kaiser Wilhelm the First: in 1876. Because of its pupil-constricting effect (Greek: miosis), pilocarpine and its relatives are also called miotics. The narrow pupil is undoubtedly a disadvantage: old people with an additional cloudiness of the lens feel impaired by the miosis. But younger patients also complain of poor twilight vision. Accordingly, pilocarpine is rarely prescribed today.

The alpha agonists clonidine and apraclonidine already mentioned belong to the older glaucoma preparations. According to the Swiss glaucoma expert Prof. Josef Flammer, clonidine is only used as a reserve drug because of its antihypertensive side effects (especially in higher concentrations).

Combination preparations

If the intraocular pressure cannot be reduced sufficiently with monotherapy or if the visual field deteriorates despite a good reduction in pressure, combinations are usually used. Beta blockers with carbonic anhydrase inhibitors and beta blockers with prostaglandin derivatives are available as fixed combinations. Combinations have several advantages for the patient: They are easier to use, less stress on the eye with preservatives than two individual substances and the risk of the “washout effect” is prevented. In special cases, however, a free two-way or even three-way therapy must be avoided.

Preservative-free preparations

In recent years, the drug options have been expanded to include preparations, without which some patients would hardly be able to perform local antiglaucoma therapy. As described in detail in our chapter on glaucoma and dry eye, not only do many glaucoma patients have a problem with the tear film - in quite a few of those affected, the preservative in the eye drops triggered a so-called “sicca” problem or exacerbated an existing tear film disorder. In the meantime, practically all the classes of active ingredients mentioned here are available in a preservative-free version - i.e. in single doses or in other formulations that do not use benzalkonium chloride (by far the most common preservative in ophthalmology).

This is undoubtedly a breakthrough - also because today prostaglandins can also be produced without preservatives. Both bimatoprost and tafluprost and latanoprost are in single-dose containers; There are also preservative-free combination products such as bimatoprost plus timolol.

Taking preservative-free preparations makes sense not only for patients with sensitive, dry or inflammatory eyes. Since you never know whether a pressure-lowering operation will one day be necessary, renouncing benzalkonium chloride is good for your conjunctiva, as the healing tendency required after an operation can be disturbed by years of exposure to this preservative. Patients with glaucoma and dry eye should also use a preservative-free tear substitute in addition to a preservative-free antiglaucoma. There are different versions of these, in single servings or in special bottles (such as the one in which the disaccharide trehalose is offered) that do not require preservatives.