The third class of medication used to reduce IOP is the alpha agonists, which are relatively commonly used but less so than beta blockers or PGAs. Their principal beneficial effect is to decrease aqueous production but they may have a lesser effect on increasing outflow. (5)
If a patient is using this class of medication, it will probably be Brimonidine (Alphagan or generics). Although about as effective as the first two classes of IOP-reducing medications discussed, the reason alpha agonists are not favoured is their common topical adverse effects, namely allergic follicular conjunctivitis and moderate to severe hyperaemia.
Systemic side-effects can include a dry nose and mouth, tiredness, drowsiness, depression and headaches (Figure 2).