Drugs for Glaucoma

Question 1

the iris circular muscle will _ the pupil to cause _

Answer 1

constrict

miosis

Question 2

iris circular muscles effect is due to activation of _ receptor

Answer 2

M3

parasympathetic

Question 3

iris radial muscle _ the pupil to cause _

its effect is due to the activation of _ _ receptors which is coupled to a _ protein

Answer 3

dilate

mydriasis

a1 adrenergic receptors

Gq protein

sympathetic

Question 4

ciliary muscle causes _ of the eye for _ vision. It also opens up the trabecular meshwork improving outflow of aqueous humor into the canal of _, decreasing _ pressure. _ receptors contract the muscle.

Answer 4

accomodation (increase curavature of the lens_

near

shclemm

intraocular pressure

M3

Question 5

ciliary epithelium produces _

_ _ receptor activation nincreases humor production and is coupled to a _ protein

_ _ receptor activation decreases humor production and is coupled to a _ protein

Answer 5

aqueos humor

B adrenergic receptor; Gs protein

A2 adrenergic receptor; Gi protein

sympathetic nervous system regulated ( humor production) + carbonic anhydrase

Question 6

what regulates the production of aqeuous humor

Answer 6

sympathetic nervous system (b and a2)

carbonic anhydrase

Question 7

what is the role of carbonic anhydrase

Answer 7

it transports bicarbonate and sodium ions from the ciliary body to the aqueous humor

the increase osmotic pressure enhances water transport into the humor increasing its volume

Question 8

what are the two methods of aqueous humor outflow

Answer 8

conventional flow through the canal of schlemm

and the uveosacral/unconventional flow

Question 9

conventional outflow is controlled by _ receptors (parasympathetic)

it increases outflow by?

Answer 9

M receptors (M3)

contracts ciliary muscle
contract iris of circular muscle

Question 10

prostaglanding _ improves uveoscleral outflow : this outflow is controlled by the _ nervous system

how does it work to increase uveoscleral and decrease conventional outflow

Answer 10

F2

sympathetic

decreased conventional : A1 receptors to contract the radial muscle and cause myadriasis

increased: A2 receptors relac ciliary muscle to increase uveoscleral outflow

Question 11

to facilitate an eye exam you want to cause mydriasis but not alter the normal accomodation of the eye. Wich of the following drug classes will dilate the pupil without altering accomodation?

M3 antagonists
M3 agonist
A1 adrenergic receptor agonists
a1 adrenergic receptor-antagonsits

a2 adrenergic receptor agonists

Answer 11

a1 adrenergic receptor agonist (causes myadriasis)

m3 antagonists- will affect accomodation

Question 12

glaucomoa is a group of _ disorders that lead to an _ _ associated with loss of visual sensitivity and field

Answer 12

ocular

optic neuropathy

Question 13

glaucoma can be primary or secondary

primary: open angle vs closed angle - describe the difference

secondary- is due to other diseases, trauma; distinct reason for glaucoma

Answer 13

open angle (95% of cases)- chronic progressive neuropathy with no structural abnormality in the outflow of aqueous humor

closed angle- acute partial or complete blockage of outflow that may have to be treated as an emergency

Question 14

the pathophysiology of open angle glaucoma is complex but there seems to be a link associated with _

Answer 14

IOP

(not definite)

Question 15

what are the groups of drugs we can use to REDUCE aquous humor production

Answer 15

betablockers - lol

a2 adrenergic agonists

carbonic anhydrase inhibitors (topical vs systemic)

open angle glaucoma

Question 16

what are the drugs that we use to INCREASE aqueous OUTFLOW

Answer 16

protaglandin analogs

a2 adrenergic agonists

direct cholinergic agents

inhibitors of cholinesterase

open angle glaucoma

Question 17

beta blockers MOA in open angle glaucoma

Answer 17

reduce aqueous humor production by the Ciliary body via blocking B receptors

Question 18

reasons why B blockers are commonly used?

Answer 18

convenience dosing

lack of local adverse effects

Question 19

why is timolol favored (beta blocker- used in reduction of aqueous humor production)

Answer 19

lacks anethetic effects, full antagonists

Question 20

systemic and local side effects of beta blockers

Answer 20

systemic: bradycardia (negative ionotropic, bronchospasm, hyperlipedemia, hypoglycemia, interact with calcium channel blockers)

local: ocular irritation/dry eyes

Question 21

what is the mechanism of a2 agonists

Answer 21

decrease rate of aqueous humor produciton and increase uveosclaeral outflow by relaxing the ciliary muscle

Question 22

what are the 2 a2 agonists used in open angle glaucoma

Answer 22

brimonidine (used more frequently) and apraclonidine

Question 23

adverse effects of a2 agonists

Answer 23

headache, fatigue, dry motuh

allergic rxns

Question 24

carbonic anyhydrase inhibitors
suffix-

MOA:

topical vs. systemic

use:

side effects:

Answer 24

-lamide

MOA: inhibit carbonic anhydrase and decrease osmotic pressure of aqueous humor (stops transport of bicarb and sodium + water into the AH)

topical: brinzolamide, dorzolamide

systemic: actazolamide
methazolamide

use: to decrease IOP quickly before surgery

side effects: metabolic acidosis, W/L, decreased libido, renal stones, ocular irritation/redness

Question 25

protaglandin analogs

• suffix

-MOA

• administration

side effects:

Answer 25

• prost

mechanism of action: reduce IOP by increasing uveoscleral and coventional outflow of AH

adminsitration: once daily at night (most effective at lowering IOP than any other drugs)

side effects: corenal erosions, conjunctival hyperemia, iris hyperpigmentation (IRREVERSIBLE), increased eyelash growth and pigment around eyelashes (reversible)

Question 26

cholinergic agonsits

MOA

direct acting

indirect acting

adverse reactions

Answer 26

MOA: activate M3 and increase conventional outlfow of AH

direct: pliocarpine, carbachol

indirect: echothiophate

adverse effects: miosis, headaches, periorbital pain, eyelid twitching, cataracts, iris-lens adhesions

not used frequently anymore

Question 27

treatment of opoen angle glaucoma

start with _ or an _ agent

if these fail use an alternative drug class

if monotherapy fails used combintation therapy

if intolerance of inadequate response to combination therapy use a _ or _ procedure

**nasolacrimal duct occlusion technique: apply pressure for 3 minutes ofver the nasolacrimal sac after eye drops are applied: this decreases _ that go into systemic circulation

Answer 27

b blocker
or prostaglandin

laser or surgical procedure

tears

Question 28

closed angle glaucoma is the intermittent mechanical blockage of trabecular meshwork by the peripheral _

they have fluctuations in _ that is signifigantly elevated

anatomical predisposition ot closed angle glaucoma: (3)

CAG with pupillary block

CAG without pupillary block

Answer 28

iris

IOP

predisposition: shallow Anterior chamber, narrow angle between corena and iris, tight contact between iris and lens

pupillary block- tight contact between iris and lens the flow of humor into AC is blocked (iris blocks outflow)

without pupillary block: ciliary processes push iris foward and iris blocks outflow

Question 29

treatment of closed angle glaucoma

Answer 29

we want to rapidly reduce IOP

systemic osmotic diuretics for surgert: oral glycerin or IV mannitol

Pliocarpine before surgery to induce miosis- DAG/IP3

block humor production: b blockers, a2 agonists, carbonic anhydrase inhbiitors

surgery/laser iridectomy: produce a hole in the iris to produce outflow

Question 30

drugs that promote elevation of IOP in open angle glaucoma

Answer 30

glucorticoids and topical antimuscarinics

Question 31

drugs that cause elevated IOP in closed angle glaucoma

Answer 31

any drug that causes mydriasis

• antimuscarinic, alpha 1 adrenomimetic