Glaucoma

Question 1

Prostaglandin analogue eye drop

Common indications

Answer 1

• As first-line agents to lower intra-ocular pressure in open-angle glaucoma and ocular HTN. Prostaglandin analogues are generally preferred over topical BB (the main alternative class) as they cause fewer systemic side effects

Question 2

Prostaglandin eye drops

MOA

Answer 2

• Elevated intra-ocular pressure (ocular HTN) is a risk factor for open-angle glaucoma
• Glaucoma is characterised by progressive optic nerve damage associated with visual field loss and eventually blindness
• It is usually, although not always, associatde with elevated intra-ocular pressure
• Either way, loweing intra-ocular pressure reduces glaucoma progression
• Analogues of prostaglandin F2a reduces intra-ocular pressure by increasing outflow of aqueous humour via the uveosclerl pathway

Question 3

Prostaglandin analogue

Adverse effects

Answer 3

• Pg analogue eyedrops have few systematic side effect
• Locally in the eye may cause blurred vision, conjunctival reddening (hyperaemia) and ocular irritation and pain
• They may also cause a permenant change in eye colour by increasing the amount of melatonin in stromal melanocytes of the iris
• This affects baout one in three patients and is most noticable when treatment is restricted to one eye

Question 4

Latanoprost
Warnings

Answer 4

• Contraindicated in HSV keratitis
• Cautioned in
  
  • Angle-closure glaucoma
  • Contact lens wearers
  • Significant history of ocylar viral infections
  • Risk of uveitis