terminology and guidelines for glaucoma ii - Kwaliteitskoepel

3.3 - ANTIGLAUCOMA DRUGS
It is important when selecting medical treatment of glaucoma to understand not only the aims of therapy, but also
the mode of action, side effects and contraindications of each individual medication.
It is worth remembering that the preservatives contained within topical eye drop preparations may cause inflammatory
conjunctival side effects and cytotoxic effects on the ocular surface 33-35 . It is therefore important to consider the
use of preservative-free preparations/delivery systems.
Over the past few years there has been a gradual shift in the choice of medical therapy 36-40 . Prostaglandin derivatives/prostamides
(such as bimatoprost, latanoprost and travoprost ) have in the hands of many ophthalmolgist superceded
β-blockers as their first choice. Latanoprost was approved as first-line treatment by EMEA in March 2002
while applications have also been made for bimatoprost and travoprost. The CPMP extended travoprost to first-line
treatment in April 2003. There is an ongoing debate in the scientific community regarding the different prostaglandins
and prostamides which has not yet been settled.
If the first choice monotherapy alone is not effective on IOP or not tolerated, it is preferrable to switch to any of the
other topical agents that can be initiated as monotherapy. If the first choice monotherapy is well tolerated and effective,
but not sufficient to reach the target IOP, then adjunctive therapy in the form of any other topical agent can be
initiated (see FC VII, VIII and IX).
It is rare nowadays for patients to be maintained on oral carbonic anhydrase inhibitors, because of their adverse
systemic side-effects.
INITIAL TREATMENT
First choice treatment:
A drug that a physician prefers to use as initial IOP lowering therapy.
First line treatment:
A drug that has been approved by an official controlling body (i.e. EMEA, CPMP or FDA)
for initial IOP lowering therapy.
Therapeutical trial
Where practical, topical treatment is started in one eye at a time.
The differential IOP will give a better idea of the effect, with less influence from diurnal variations.
For some drugs, a cross-over effect to the fellow eye must be taken into account 41-50 .
Therapeutic Index
It is the ratio of desired, beneficial effects to adverse effects.
Treatment is considered “effective” on IOP when the observed effect is at least equal to the
pubished average effect for the same molecule on a similar population. It must be larger than
tonometry errors / variations.
Ch. 3 - 7 EGS