optho drugs exam 3

Question 1

what are the ways we increase drug absorption across the cornea? (there are many)

Answer 1

frequent (slow elimination), high doses, lipophilic, unionized, decrease corneal thickness, increase [] to a point, increase contact time

Question 2

when is systemic drugs most prefered

Answer 2

anterior segment, ulcers that rupture through the membrane, maybe corneal stroma-depends on inflam

Question 3

what are 2 of the systemic drugs that reach high [] in the eye

Answer 3

minocycline and enrofloxacin

Question 4

what are the two antifungals we administer systemically for ocular use?

Answer 4

fluconazole, voriconazole

Question 5

it is best to send patient home with a ______(solution or ointment)

Answer 5

ointment because they increase contact time and have to be given less frequently

Question 6

polymixin B. what bacti? what route?

Answer 6

G- bacteria. almost exclusively topical because it is nephrotox (maybe ok for endotoxemia)

Question 7

bactitracin/gramicidin. what bacti? what route?

Answer 7

G+/-. not absorbed orally, topically/opth only.

Question 8

why do we not want to treat corneal ulcers with triple + hydrocortisone?

Answer 8

the steroid can allow for infection in a corneal ulcer by suppressing the immune system.

Question 9

what are our two topical antifungals

Answer 9

natamycin and voriconazole

Question 10

what is the main difference between natamycin and voriconazole?

Answer 10

natamycin is best for more superficial infections of the cornea. does not penetrate cornea. voriconazole is good for stromal or deeper fungi

Question 11

which topical antifungal has synergism with tobramycin and cefazolin

Answer 11

natamycin

Question 12

what is the drug we can use subconjunctively for refractory fungal infections. commonly for fusarium

Answer 12

amphotericin B

Question 13

what are the two virostatic drugs we can use for herpesvirus keratitis and conjunctivitis flare ups?

Answer 13

trifluridine and idoxuridine

Question 14

what are the two topical antibacterials that we reach for?

Answer 14

polymixin B and bacitracin/gramicidin

Question 15

three main categories of antinflammatories for ocular use

Answer 15

glucocortocoids, NSAIDs, immunomodulators (cyclosporine A)

Question 16

what are the three major topical GCs we use for eyes

Answer 16

topical prednisolone acetate, dexmethasone sodium phosphate, or hydrocortisone.

Question 17

which GC penetrates the intact cornea?

Answer 17

dexmethasone SP.

Question 18

which GC is available in a topical ointment?

Answer 18

Dexmethasone SP

Question 19

how do the three GCs compare in potency/peneration?

Answer 19

prednisolone acetate is basically the same as dexmethasone SP. hydrocortisone is way weaker.

Question 20

when are topical optic GCs contraindicated?

Answer 20

in the presence of corneal ulcers and with Fungal infections

Question 21

when are systemic GC and NSAIDs used?

Answer 21

topical steroids are often combined with systemic NSAIDs. like flunixin in the horse

Question 22

what is our topical immunomodular? mech of action?

Answer 22

cyclosporine A. blocks IL-2 production

Question 23

when is cyclosporine A indicated for treatment?

Answer 23

in lymphocytic infiltrates. or eosinophilic keratitis.

Question 24

t/f cyclosporine A penetrates an intact cornea?

Answer 24

FALSE. it is best for surface diseases.

Question 25

unique way we can treat anterior uveitis in equine patients?

Answer 25

suprachoroidal implants of cyclosporine A. can deliver drug for months to years

Question 26

for the Autonomic NS, what receptors are in the eye that drugs can act on?

Answer 26

A1, B, muscarinic

Question 27

what type of ANS drug do we use most commonly?

Answer 27

tropicamide and atropine.

Question 28

when is it appropriate to use tropicamide (ANS drug)

Answer 28

used to dilate the eye prior to exam. only works for 1-2 hours. not as a treatment but to work on eye.

Question 29

when do you use atropine?

Answer 29

long acting. to relieve pain when inflammation is constantly trying to constrict the pupil. can prevent synechiae (adhering), or preventing glaucoma.

Question 30

negative side effect of atropine?

Answer 30

decreased tear production- monitor dry eye. ileus?

Question 31

what are our three drugs that cause miosis

Answer 31

pilocarpine, carbachol, demecarium bromide. these are cholinergic agonist

Question 32

which miosis inducing drug is most commonly used? for what?

Answer 32

pilocarpine. used to treat dye eye in dogs that have a neurogenic cause.

Question 33

which two drugs are commonly used to treat glaucoma together

Answer 33

timolol, and dorzolamide. decrease aqueous humor production/secretion.

Question 34

what is latanoprost used for? what species is it not useful in?

Answer 34

used for glaucoma because it increases outflow of aqueous humor. doesn't work in cats.

Question 35

when are topical anesthetics contraindicated?

Answer 35

as therapy for ulcerative keratitis. toxic to the epithelium and won't heal.

Question 36

how does latanoprost treat glaucoma?

Answer 36

lowers intraocular pressure by increasing outflow of aqueous humor.