Drugs Used for Glaucoma Flashcards
What is the function of the iris circular m.?
What receptors act on it?
Constriction of the pupil to cause miosis
M3 receptors
What is the function of the iris radial m.?
What receptors act on it?
Dilation of the pupil to cause mydriasis
Alpha-1 receptors
What is the function of the ciliary m.?
What receptors act on it?
Causes accomodation and opens the trabecular meshwork to improve outflow of aqueous humor
M3 receptors
Which receptors are acted on in the ciliary epithelium to increase or decreased humor production?
Increase - beta
Decrease - alpha-2
What is first-line therapy for treatment of glaucoma? (3)
Prostaglandin analogues
Beta-blockers (Timolol)
Brimonidine
What is second-line therapy for treatment of glaucoma? (3)
Pilocarpine
Apraclonidine
Topical carbonic anhydrase inhibitors
Why are beta-blockers useful in treatment of glaucoma?
Why is Timolol favored?
Dosing is easy and there are fever side-effects.
It does not have the same local anesthetic effects.
What are the local adverse-effects of beta blockers?
Stinging, dry eye, blurred vision, blepharitis.
Bradycardia, bronchospasm, exacerbation of hypoglycemia.
What drug may interact with beta-blockers and increase the risk of cardiac depression and heart block?
Verapamil
What is the MOA for Prostaglandin analogues in treatment of glaucoma?
How is it given?
What are the local side effects?
What is the suffix for these drugs?
Reduce IOP by increasing the uveoscleral and trabecular outflow of aqueous humor.
1 drop nightly
Corneal erosions, hyperemia, iris pigmentation (irreversible), hypertrichosis.
-prost
Bimatoprost is best.
What alpha-2 agonist is first-line?
What is the main local side-effect?
What are the major systemic side-effects?
Brimonidine
Allergic reaction around the eye.
Dizziness, fatigue, dry mouth, bradycardia and hypotension.
What is the algorithm for treatment of open angle glaucoma?
- Start with a beta-blocker.
- If beta-blocker is contraindicated, then switch to another first-line agent (PGs or Brimonidine).
- If contraindicated to all the above, use carbonic anhydrase inhibitors (second-line therapy)
What is the goal for treatment of closed angle glaucoma acutely?
What is the drug of choice before surgery?
Rapidly reduce IOP.
- oral glycerin 1-2 g/kg
- IV mannitol 1-2 g/kg
Pilocarpine
What drugs can induce increased IOP in open angle glaucoma? (2)
Glucocorticoids
Topical antimuscarinics
What drugs can trigger angle closure in closed angle glaucoma?
Anything that can cause mydriasis
