Glaucoma Drugs (Konorev)

Question 1

What are the two muscles that make up the iris and what is there function?

Answer 1

iris “circular” muscle or sphincter pupillae - constricts pupil (miosis)
iris “radial” muscle or dilator pupillae - dilates pupil (mydriasis)

Question 2

receptor for iris “circular” muscle or sphincter pupillae

Answer 2

M3 - Gq pathway; remember if you’re constricting the pupil it is a parasympathetic action

Question 3

receptor for iris “radial” muscle or dilator pupillae

Answer 3

alpha 2 - Gq pathway; remember if you’re dilating the pupil it is a sympathetic action

Question 4

Normal physiology of aqueous humor production

Answer 4

produced by the ciliary epithelium; Beta receptors stimulate its production (Gs); alpha 2 receptors inhibit its production (Gi); carbonic anhydrase enzyme increases it production

Question 5

What are the 3 classes drugs that inhibit aqueous humor production?

Answer 5

1. beta blockers - Timolol (favored), Betaxolol, Timolol, Carteolol, Metipranolol, Levobunolol
2. alpha 2 agonist - Apraclonidine and Brimonidine
3. CA inhibitors:
   topicals - Brinzolamide and Dorzolamide
   systemics - Acetazolamide and Methazolamide

Question 6

What are the 5 beta blockers used to decrease aqueous humor production in glaucoma?

Answer 6

Timolol (favored), Betaxolol, Carteolol, Metipranolol, Levobunolol

Question 7

Which beta blocker is favored for the use of glaucoma and why?

Answer 7

Tamolol; lacks local anesthetic effects (more favorable for glaucoma patients); available as a generic and is a full antagonist

Question 8

Adverse effects of beta blockers?

Answer 8

systemic parasympathetic effects; local effects - ocular irritation and dry eyes

Question 9

What are the two alpha 2 receptor agonist that is used to decrease aqueous humor production in glaucoma?

Answer 9

Brimonidine and Apraclonidine (less used due to allergies)

Question 10

Adverse effects of alpha 2 receptor agonist?

Answer 10

Headaches, fatigue and dry mouth; local - allergic reactions

Question 11

What are the two classes of carbonic anhydrase inhibitors used to treat glaucoma?

Answer 11

“zolamide’s”
topicals - Brinzolamide and Dorzolamide
systemics - Acetazolamide and Methazolamide

Question 12

Brinzolamide and Dorzolamide

Answer 12

topical carbonic anhydrase inhibitors used to treat glaucoma

Question 13

Acetazolamide and Methazolamide

Answer 13

systemic carbonic anhydrase inhibitors used to treat glaucoma

Question 14

What are the adverse effects of carbonic anhydrase inhibitors?

Answer 14

Nausea, diarrhea, loss of appetites, altered taste
Weight loss, paresthesias, renal stones and decreased libido

Question 15

Which prostaglandin analog is most effective in lowering intraocular pressure (IOP)?

Answer 15

Bimatroprost

Question 16

What are the 3 classes of drugs that is used to glaucoma by increasing aqueous humor outflow?

Answer 16

1. Cholinergic agonist (direct) - Pilocarpine and Carbachol
2. Cholinesterase inhibitor (indirect cholinergic agonist) - Echothiophate
3. Prostaglandin F2alpha analogs - Bimatoprost (favored), Latanoprost and Travoprost

Question 17

MOA of cholinergic agonist in treating glaucoma?

Answer 17

activate the M3 receptor (Gq) on the ciliary muscles; increases the outflow of aqueous humor

Question 18

MOA of cholinesterase inhibitor in treating glaucoma?

Answer 18

inhibits acetylchlinesterae inhibitor; allowing more acetylcholine to be available for activation of the M3 receptor on the ciliary muscle to increase the outflow of aqueous humor

Question 19

Adverse effects of the cholinergic agonist (both direct and indirect)?

Answer 19

headaches and periorbital pain, miosis, eyelid twitching, myopia, cataracts, and iris-lens adhesions

Question 20

Pilocarpine and Carbachol

Answer 20

Cholinergic agonist (direct) agents used to treat glaucoma by activating the M3 receptor (Gq) on the ciliary muscles; increases the outflow of aqueous humor

Question 21

Echothiophate

Answer 21

Cholinesterase inhibitor (indirect cholinergic agonist) used to treat glaucoma by inhibiting acetylchlinesterae inhibitor; allowing more acetylcholine to be available for activation of the M3 receptor on the ciliary muscle to increase the outflow of aqueous humor

Question 22

What are the first line treatment for open angle glaucoma?

Answer 22

beta blockers - Timolol (favored), Betaxolol, Timolol, Carteolol, Metipranolol, Levobunolol
OR
Prastaglandin F2alpha analogs - Bimatoprost (favored), Latanoprost and Travoprost

Question 23

What are the 3 prostaglandin analogs and what is their MOA?

Answer 23

Bimatoprost (favored), Latanoprost and Travoprost; increase aqueous humor outflow

Question 24

Adverse effects of prostaglandin analogs?

Answer 24

Corneal erosions, conjunctival hyperemia, iris hyperpigmentation (irreversible), hypertrichosis (hyperpigmentation around eyelashes and eyelids)

Question 25

Which class of drug can cause hypertrichosis?

Answer 25

prostaglandin analogs; Bimatoprost (favored), Latanoprost and Travoprost; hyperpigmentation around eyelashes and eyelids

Question 26

What are the two types of closed angle glaucoma (CAG)?

Answer 26

With pupillary block - tight contact between iris and the lens; blocks flow of aqueous humor into anterior chamber

Without pupillary block - ciliary processes are located in a way that they push the iris forward and block outflow

Question 27

Treatment of closed angle glaucoma (CAG)?

Answer 27

1. decreased IOP - Give systemic diuretics - Oral Glycerin or IV Mannitol
2. induce miosis - Pilocarpine
3. Reduce aqueous humor - beta blockers, alpha 2 agonist or CA inhibitors
4. Surgery or laser iridectomy