What types of treatment methods are available for
glaucoma?
The only proven method
of treatment for glaucoma is reducing the pressure inside the eye.
There are three ways to lower the eye pressure for glaucoma:
medications (usually taken as eye drops), laser treatment, and
surgical treatment. For most patients with newly diagnosed or
easily controlled glaucoma, one or more types of eye drops are used
daily. Some patients' eye pressures cannot be adequately
controlled with eye drops (or the patients have allergies to or
side effects from medication) and laser treatment or surgery is
needed. Sometimes, laser treatment can be performed first to treat
open-angle glaucoma, but medication is frequently needed later. If
medication and laser both fail to control intraocular pressure,
surgery (usually a trabeculectomy) becomes necessary. For severe
cases of glaucoma, less common procedures (such as a glaucoma
implant) are performed.
Laser treatment is required early in
most cases of angle-closure glaucoma and is used as an alternative
or supplement to treatment in open-angle glaucoma.
The goal in treating glaucoma is to
preserve the patient's vision by reducing intraocular (inside the
eye) pressure and protecting the optic nerve.
Medical
therapy
There are several
classes of medications used to treat glaucoma, with many advances
having been made over the past several years. Each medication has a
different mechanism of reducing pressure, either working to reduce
the production of aqueous humor (fluid in the front part of the
eye), or to reduce the resistance to the outflow of aqueous. These
medications can be used individually or together to complement each
other. Side effects can occur are uncommon. Your doctor will
explain which medication is right for you. Please let your doctor
know if you believe you are experiencing side effects from your
glaucoma medication.
The following medications can be used
to treat glaucoma:
- Beta-blockers:
Beta-blockers (betaxolol, carteolol, levobunolol, metipranolol,
timolol) work by reducing aqueous production. They have a long,
proven track record of effectiveness and are used once or twice
daily. They are inexpensive and safe for most patients, but
beta-blockers should NOT be used by patients with asthma, chronic
lung disease, heart-block, hypotension, or severe heart
failure.
- Alpha-2 agonists:
These medications (apraclonidine, brimonidine) also work by
reducing aqueous production. They are slightly less effective than
beta-blockers and are used twice daily. Their side effects can
include an allergic reaction, redness or irritation in the eyes,
occasional headaches, and--in rare instances-- a decrease in mental
alertness.
- Carbonic anhydrase inhibitors: These medications work by reducing aqueous
production. The side effects of oral carbonic anhydrase inhibitors
(acetazolamide, methazolamide) include fatigue, loss of appetite,
numbness and/or tingling in the hands and feet, and stomach upset.
When used as a topical medication (brinzolamide, dorzolamide),
carbonic anhydrase inhibitors are a little less effective, but
there are very few side effects except occasional allergic
reactions.
- Prostaglandins:
Prostaglandins (bimatoprost, latanoprost, travoprost, unoprostone)
work by decreasing the resistance to aqueous outflow and have been
shown to be very effective in reducing intraocular pressure. Side
effects include redness, irritation or inflammation in the eye,
darkening of the iris color and an increased growth of
eyelashes.
- Miotics: Miotics
such as carbachol, echothiophate, and pilocarpine are
effective and inexpensive. However, their side effects of brow ache
and dim or blurred vision have reduced their use.
- Combination
medication:
Cosopt
(timolol and dorzolamide) is used twice daily. The medication has
two glaucoma medications in one bottle, thus reducing the number of
different glaucoma medication bottles needed.