Opthalamic Drugs

Question 1

The topical route is used to target which structures of the eye? (4)

Answer 1

Conjunctiva
Cornea
Anterior Uvea
Eye Lids

Question 2

Systemic route is used to target which structures of the eye? (4)

Answer 2

Eye Lids
Posterior Segment
Optic nerve
Anterior Segment

Question 3

Which structures of the eye serve as drug reservoirs? (3)

Answer 3

Cornea
Lens
Uveal pigment (melanin)

Question 4

Which drugs are formulated for topical administration?

Answer 4

Solutions, suspensions & ointments

Question 5

Which route of admin allows for depot storage & achieves [high] in the ANTERIOR chamber?

Answer 5

Subconjunctival Therapy

Question 6

Which route of admin achieves very high [drug] by injection of the drug into the AQUEOUS/VITREOUS HUMOR?

Answer 6

Intracameral Therapy

Question 7

Absorption after TOPICAL admin is determined by what? (TQ)

Answer 7

Amt. of time drug hangs around
Nasolacrimal drainage
Binding to tear proteins
Metabolism by tear & tissue proteins
Diffusion across cornea & conjunctiva

Question 8

Systemic distribution of TOPICALLY admin. drugs?

Answer 8

Nasal mucosal absorption
Local ocular distribution
How easily is passes the cornea & accumulates in the aqueous humor
Does is bind melanin?

Question 9

Enzymatic biotransformation occurs in the eye via _________.

Answer 9

Esterases

Question 10

Which type of drugs are more effective in the eye?

Answer 10

pro-drugs

Question 11

What 2 agents cause MYDRIASIS (dilation) of the pupil?

Answer 11

Sympathomimetic drugs

Parasympatholytic drugs

Question 12

What agent causes MIOSIS (constr.) of the pupil?

Answer 12

Parasympathomimetic drugs

Question 13

What agents cause pinpoint pupils?

Answer 13

Opioids

Question 14

What should you always do before using anti-biotics on the eyes? (TQ)

Answer 14

ID the pathogen!!

NEVER TX NON-INFECTED EYES (resistance)

Question 15

What 3 anti-biotics are frequently used to TX eyes in Vet med?

Answer 15

Chloramphenicol
Fluoroquinolones (Cipro)
Gentamicin-Amikacin-Tobramycin combo

Question 16

What drugs are your 1st choice for TXing corneal ulcers & bacterial conjunctivits?

Answer 16

BNP

NPG

Question 17

Which anti-microbial is the 1st choice in small animal practice? What’s the problem?

Answer 17

Chloramphenicol

won’t TX Pseudomonas

Question 18

Which anti-microbial will penetrate an intact cornea?

Answer 18

Ciprofloxacin

Question 19

Which drugs do you use to TX keratomycosis?

Answer 19

Polyene antibiotics
Imidazoles
Nucleoside analogs

Question 20

What 3 drugs do you use equal amts of to TX corneal ulcers?

Answer 20

Natamycin
Tobramycin
Cefazolin

Question 21

What can you use to cause proteinase inhibition (thereby TXing corneal ulcers)?

Answer 21

Plasma alpha2-macroglobulin
Chelating agents (EDTA, Acetylcysteine, & Tetracyclines)

Question 22

How can you decrease intraocular pressure & TX glaucoma? (4)

Answer 22

Decr. aqueous humor production
Incr. aqueous humor outflow
Neuroprotection from glutamate signalling
Surgery?

Question 23

What are 3 topical prostaglandin analogs used to TX glaucoma?

Answer 23

Latanoprost
Bimatoprost
Travoprost

Question 24

What are 3 beta-adrenoceptor antagonists used to TX glaucoma?

Answer 24

Timolol
Metipranolol
Betaxolol

Question 25

What drugs reduce formation of bicarbonate & reduce fluid transport (glaucoma TX)?

Answer 25

carbonic anhydrase inhibitors

Question 26

What drug increases aqueous outflow via increasing trabecular outflow?

Answer 26

Pilocarpine (topical miotic)

Question 27

What Ca channel blocker can be used to prevent excitotoxicty in glaucoma?

Answer 27

Amlodipine

Question 28

What NMDA channel blocker can be used to prevent excitotoxicity in glaucoma?

Answer 28

Memantine

Question 29

What type of drugs can be used to TX allergic conjunctivits? (TQ)

Answer 29

Antihistamines | Mast-cell stabilizers

Question 30

What drugs can you NOT use on a damaged cornea? (TQ)

Answer 30

Glucocorticoids

Question 31

What are the main anatagonists used in Vet med?

Answer 31

Muscarinic antagonists

Question 32

What disinfectant can be used when DXing eye issues?

Answer 32

2% povidone iodine

Question 33

What is the main route of entry & absorption pathway into the eye?

Answer 33

Corneal route | Cornea--> Aqueous humor--> Iris--> systemic circulation

Question 34

How can you change the elimination half life of eye meds? (3)

Answer 34

change tear production change drainage change blinking rate

Question 35

What 2 drugs are subconjunctival therapy used for?

Answer 35

Antibiotics | Corticosteriods

Question 36

What are the 2 host-derived proteinases that lead to corneal ulceration?

Answer 36

``` zinc metalloproteinases (MMPs) Neutrophil serine proteinase ```

Question 37

What are the systemic proteinase inhibitors used to TX corneal ulcres?

Answer 37

Homologous plasma or serum- topically | Combo w/ EDTA or Acetylcysteine

Question 38

How does heparin inhibit proteinases? (TQ)

Answer 38

Impedes extravasation of leukocytes

Question 39

Which types of proteinases do Ilomastat inhibit?

Answer 39

Inhibits endogenous & Pseudomonas proteinases

Question 40

Which drug class affects trabecular outflow?

Answer 40

Muscarinic agonists

Question 41

Which drug class affects uveoscleral outflow?

Answer 41

Prostaglandin agonists

Question 42

Which drug classes affect aqueous humor inflow? (3)

Answer 42

Beta- blockers Alpha 2 Agonists Carbonic Anhydrase Inhibitors

Question 43

What is the MOA of Beta-blockers? | (Timolol, Metipranolo, & Betaxolol)

Answer 43

non-selective drugs | blocks cAMP-PKA pathways and reduces aqueous humor production

Question 44

What receptor do prostaglandin analogs bind to?

Answer 44

Gq receptor - Phospholipase C- IP3-Ca pathway

Question 45

What is the MOA of Alpha 2 Agonists? (TQ)

Answer 45

Inhibits adenylate cyclase | reduced Na/K/ATPase activity

Question 46

What is the MOA of carbonic anhydrase inhibitors?

Answer 46

reduce formation of bicarbonate & fluid transport

Question 47

Which anti-inflammatory is immunosuppressive & highly lipophilic? (TQ)

Answer 47

Cyclosporin A

Question 48

What drug is sympatholytic & causes miosis?

Answer 48

Timolol acetate

Question 49

What 3 drugs are parasympatholytic & cause mydriasis?

Answer 49

Atropine Tropicamide Scopolamine

Question 50

Which 2 drugs are sympthomimetic drugs & cause mydriasis? (used to TX anterior uveitis)

Answer 50

Phenylephrine | Epinephrine

Question 51

What local anaesthetics can be used as DX aids?

Answer 51

Proparacaine & Tetracaine --> topical | Lidocaine & Bupivacaine --> infiltration anaesthetics