Prostaglandin Analogues (PGAs) are currently the most common first-line medications for treating open-angle glaucoma due to their high efficacy and convenience (administered just once a day).
Mechanism of Action
Prostaglandins work by increasing the drainage of intraocular fluid out of the eye, primarily through the uveoscleral pathway (the secondary drainage route). Their effectiveness in lowering pressure is among the highest of all medications, typically reducing IOP by 25% to 35% from baseline.
Typical Side Effects
Unlike some other medication classes, PGAs have almost no systemic (whole-body) side effects. However, they may cause local ocular side effects, including: overgrowth and lengthening of the eyelashes, redness in the eyes, darkening of the iris color (an irreversible change, especially noticeable in hazel/green-brown eyes), and periorbital fat loss, which can cause the eye to appear slightly sunken.