Glaucoma Drugs

Question 1

CHOLINOMIMETICS

Answer 1

Glaucoma cholinomimetics:

1. Pilocarpine
2. Carbachol
3. Echothiophate (AchEsterase inhibitor long acting)
4. Demecarium (AchEsterase inhibitor)

MECHANISM : M3 R agonist!!

• pupil sphincter muscle–>pupil constriction (miosis)
• ciliary muscle contraction–>opens the trabecular meshwork–> facilitates aqueous humor drainage into the Schlemm’s canal–>decrease IOP

INDICATION
-Glaucoma: topical drops

SIDE EFFECTS:

• irritation of the eye
• increased tearing
• headache
• blurred vision

Question 2

ALPHA AGONISTS

Answer 2

Glaucoma Alpha agonists:

1. Epinephrine (non selective)
2. Dipivefrin (non selective)
3. Apraclonidine (alpha2 agonist)
4. Brimonidine (alpha2 agonist)

MECHANISM
alpha 1 R: pupil sphincter muscle–> pupil constriction (miosis)
-decrease the aqueous humor production
-increase the outflow through the Schlemm’s canal

INDICATION
-Glaucoma: topical drops
-Horner’s triad diagnosis: sympathetic trunk lesion presenting 3 characteristic signs:
1.miosis
2.ptosis
3.enophtalmos
Horner pupil will dilate, but normal pupil does not.

SIDE EFFECTS
no CV side effects

Question 3

BETA BLOCKERS

Answer 3

Glaucoma Beta blockers:

1. Timolol (non selective)
2. Betaxolol (Beta1 selective)
3. Carteolol (non selective)
4. Levobunolol (non selective)
5. Metipranolol (non selective)

MECHANISM
(B2 stimulation: relaxation–> Schlemm’s canal close)
Beta R antagonist in ciliary muscle
-reduce aqueous humor production

INDICATION
-Glaucoma: topical drops

SIDE EFFECTS
contraindicated in airways disease (eg.asthma)

Question 4

CARBONIC ANHYDRASE INHIBITORS

Answer 4

Glaucoma Carbonic anhydrase inhibitors:

1. Dorzolamine (topical)
2. Brinzolamide (topical)
3. Acetazolamide (oral)
4. Dichlorphenamide (oral)
5. Methazolamde (oral)

MECHANISM
-decrease production of aqueous humor (lack of HCO3)

INDICATION
-Glaucoma

SIDE EFFECTS
-ocular burning, itching

Question 5

PROSTAGLANDINS

Answer 5

Glaucoma Prostaglandins:

1. Latanoprost
2. Bimatoprost
3. Travoprost
4. Unoprostone

MECHANISM
Prostaglandin F Receptor agonist
-facilitate outflow through Schlemm’s canal by increasing the sclera’s permeability to aqueous humor

INDICATION
-Glaucoma: topical

SIDE EFFECTS

• blurred vision
• redness of the eye
• itchy sensation