NHMRC Glaucoma Guidelines - ANZGIG

NHMRC GUIDELINES FOR THE SCREENING, PROGNOSIS, DIAGNOSIS, MANAGEMENT AND PREVENTION OF GLAUCOMA
Chapter 9 – Medication
Changing medication regimens
Change in well-tolerated medication regimens and the use of additional medications are only
supported in situations where target IOP has not been reached despite the patient’s adherence
to the regimen. If the initial choice of medication management was ineffective in achieving target
IOP, and the IOP response to the medication was poor, switching to a different class of medication
is justified. A wash-out period is required followed by a repeated one-eye trial. Exceeding the
recommended dosage will not lower IOP further, and might increase the likelihood of side effects.
In the presence of an adequate but non-target IOP response, an additional medication may be
required to achieve the target. If more than two topical medications are required to lower the
IOP, then other treatment options should be considered. Significant side effects are frequently
encountered with systemic medication (EGS 2003). In this instance laser therapy or surgery are
considered as second choice management options.
Evidence Statements
• Evidence strongly indicates that, where the medication regimen is well tolerated, the main indicator for
changing it is failure to reach target intraocular pressures.
• Evidence strongly supports substitution rather than addition of medication when treatment is ineffective.
• Evidence strongly supports that when two or more topical medications are ineffective, consideration is
given to laser therapy or surgery instead of systemic medications.
Medication in acute angle closure crisis
For acute angle closure, medical management is usually initiated to lower IOP, to reduce pain and
to clear corneal oedema in preparation for laser therapy. Medications that suppress aqueous humor
formation (beta-adrenergic antagonists, carbonic anhydrase inhibitors) may be ineffective because
they will have decreased capacity to reduce aqueous formation if the ciliary body is ischemic
(AAO 2005).
Pre-operative cholinergics (miotics) may improve the effectiveness of laser iridotomy or iridoplasty.
For emergency cases, the use of systemic medications such as oral/parenteral hyperosmotic
medications and oral/parenteral carbonic anhydrase inhibitors should be considered in order to
rapidly reduce IOP and avoid permanent damage to both the posterior and anterior segments of
the eye. Topical timolol and brimonidine/apraclonidine may be considered (Singapore Ministry
of Health [SMOH] 2005) along with topical carbonic anhydrase inhibitors. Post-operatively, topical
anti-inflammatory medications are usually also indicated. Saw, Gazzard and Friedman (2003)
suggest introducing latanoprost additive medication before glaucoma surgery. Latanoprost appears
particularly promising if the IOP is less than 25mmHg, and/or when there have been fewer than
three previous failed incisional glaucoma operations.
Evidence Statement
• Evidence strongly supports using adjunct medications including cholinergics (miotics), hyperosmotic
medications and carbonic anhydrase inhibitors to rapidly reduce intraocular pressure prior to surgery.
National Health and Medical Research Council 121