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Flashcards in Pharmacology Deck (28)
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1

List the main routes of administration of ocular drugs

Topical (drops, ointments)
Subconjunctival
Subtenons
Ocular injection (intravitreal, intracameral)

2

Which type of drug - hydrophilic or lipophilic - can penetrate the ocular epithelium?

Lipophilic (lipid soluble drugs), since epithelium is hydrophobic and lipophilic

3

Which type of drug - hydrophilic or lipophilic - can penetrate the ocular stroma?

Hydrophilic (water soluble drugs), since stroma is hydrophilic and lipophobic

4

Chloramphenicol is both hydrophilic and lipophilic. True/False?

True
Penetrates cornea easily

5

What effect does ocular surface inflammation have on the hydrophobic nature of the ocular epithelium?

Reduces hydrophobic nature

6

Tear film may impede drug penetration. Why?

Lipid layer will impede hydrophilic agents

7

Hydrophilic drugs are limited by epithelium/stroma and lipophilic drugs are limited by epithelium/stroma

Hydrophilic drugs are limited by epithelium and lipophilic drugs are limited by stroma

8

How can topical steroid be made more hydrophobic (what can be added)?

Alcohol (acetate)

9

How can topical steroid be made more hydrophilic (what can be added)?

Phosphate

10

Prednisolone acetate is hydrophilic. True/False?

False
Hydrophobic (contains acetate)

11

Prednisolone phosphate has good penetration. True/False?

False
It is hydrophilic and thus doesn't penetrate ocular epithelium well (epithelium is hydrophobic)

12

What can be added to a topical drug to increase corneal penetration?

Benzalkonium

13

Give an example of a drug that can be administered through the subconjunctival route

Steroid

14

Give an example of a drug that can be administered through the subtenons route

Local anaesthetic (via cannula)

15

List some anti-inflammatory agents for ocular disease

Steroid
NSAIDs
Anti-histamines
Mast cell stabilisers

16

When are topical steroids usually used for ocular disease?

Post-op cataracts
Uveitis
Prevent corneal graft rejection

17

List some local ocular side effects of steroids

Acute glaucoma
Cataract
Exacerbation of viral infection

18

How do glaucoma drops basically work?

Decrease production of fluid and/or increase fluid outflow/drainage from the eye through the trabecular meshwork

19

Which class of drug is 1st line for glaucoma and how does it work?

Prostanoids - Latanoprost (Xalatan)
Opens up uveal-scleral outflow (makes vessels leakier to allow fluid drainage)

20

How to beta-blockers and carbonic anhydrase inhibitors help in glaucoma?

Block ciliary body and thus decrease fluid production

21

Give an example of a carbonic anhydrase inhibitor

Topical Dorzolamide
Systemic Acetazolamide

22

How do alpha agonists help in glaucoma? Give an example of one

Brimonidine
Make all vessels leakier and thus increase fluid drainage

23

How do parasympathomimetics help in glaucoma? Give an example of one

Pilocarpine
Pull iris tight together to open up trabecular meshwork and enable fluid drainage

24

Name a pro + con of intravitreal drug administration

Deliver effective concn of drug
Can be toxic to retina

25

When is intravitreal drug administration mainly used?

Administering antibiotic in exophthalmitis
Intra-ocular steroids

26

What effect does local anaesthetic have on the eye?

Blocks sodium channels + impedes nerve conduction so can keep eye open

27

Which dye is useful for viewing corneal abrasions?

Fluorescein dye

28

What do mydriatics do? Give an example and side effect

Block parasympathetic supply to iris, causing pupil dilation
Tropicamide
Side effect: blurring, acute glaucoma