Pharmacology

Question 1

What kind of drugs do the corneal epithelium like?

Answer 1

Lipophilic

Question 2

What kind of drugs do the corneal stroma like?

Answer 2

Hydrophilic

Question 3

Which drug has both a lipophilic and hydrophilic component

Answer 3

Chloramphenicol

Question 4

How can a drug be made more lipophilic?

Answer 4

Addition of an alcohol

Question 5

How can drugs be made more hydrophillic?

Answer 5

Addition of a phosphate group

Question 6

Which steroid is given for an uninflamed cornea?

Answer 6

Prednisolone acetate

Acetate group - hydrophobic so good in the epithelium.

Question 7

Which steroid is given for corneal disease?

Answer 7

Prednisolone phosphate.

Phosphate- hydrophillic so good in the stroma

Question 8

How can hydrophilic drugs be better absorbed into the stroma?

Answer 8

Benzalkonium.

It disrupts the lipid layer of the tear film

Question 9

What is the name of the benzalkonium?

Answer 9

Bimatoprost

Question 10

How are topical steroids incorporated systemically?

Answer 10

Tears spread the topical drug into the punctum which leads to the nasopharynx so is swallowed

Question 11

How can steroids be prevented from spreading systemically?

Answer 11

Pressing on punctum (nasal side) stops the drops getting to the nasopharynx.

Question 12

What side effect may be present with topical steroids?

Answer 12

Bad taste in mouth

Question 13

When are steroids given intravitreally?

Answer 13

Wet macular degeneration

Question 14

When are topical steroids used? (3)

Answer 14

Post op cataracts to prevent inflammation
Uveitis
Preventing corneal graft rejection

Question 15

What are the signs of uveitis?

Answer 15

Injecting vessels
Photophobia
Misshapen pupil
WBC on slit lamp

Question 16

What signs are bad in a corneal graft?

Answer 16

New blood vessels.

Graft rejection line - darker infiltrate inferiorly

Question 17

What are the local side effects of steroids?

Answer 17

Cataracts
Glaucoma
Exacerbation of viral infection

Question 18

In what infective ocular process should steroids not be used?

Answer 18

Viral conjunctivitis

Question 19

What systemic side effects can steroids cause?

Answer 19

Osteoporosis
Weight gain
Diabetes
Gastric ulceration

Question 20

What dosage of steroids should be given for temporal arteritis?

Answer 20

80mg

high!

Question 21

What is glaucoma?

Answer 21

Progressive optic neuropathy resulting in loss of peripheral vision

Question 22

What are the risk factors for getting glaucoma?

Answer 22

Family history
Over 40
Steroids
Diabetes

Question 23

What is thought to cause glaucoma?

Answer 23

A raised intracranial pressure

Question 24

What investigation needs to be done in glaucoma?

Answer 24

Visual field test.

If double sided then driving is not allowed.

Question 25

Which glaucoma treatment can be given by drops?

Answer 25

Pilocarpine - miotic Latanoprost Timolol - B blocker

Question 26

What is acetazolamide?

Answer 26

reduces ICP by reducing production of aqueous humour. Given IV/IM.

Question 27

What is important to note with latanoprost?

Answer 27

Can change the colour of the iris

Question 28

Which drug is given first in glaucoma?

Answer 28

Prostanoids e.g. latanoprost

Question 29

What is anti-VEGF given for?

Answer 29

To prevent new blood vessels from forming

Question 30

When are drugs given intra-vitreally?

Answer 30

Endophthalmitis

Question 31

Why can local anaesthetic not be used regularly?

Answer 31

Stops epithelium from regenerating so prevents healing

Question 32

How and why is fluorescein used?

Answer 32

With a blue light. | Shows corneal abrasion

Question 33

What is tonometry?

Answer 33

Measures pressure

Question 34

How can fluorescein be used to diagnose nasolacrimal duct obstruction?

Answer 34

Will run out of lateral sides of eye instead of into the puncture.

Question 35

How do mydriatics work?

Answer 35

Cause pupil dilation by blocking parasympathetic (CN III) supply to ciliary muscles

Question 36

What damage can ethambutol cause to the eye?

Answer 36

Optic neuropathy

Question 37

What drug can cause maculopathy?

Answer 37

Chloroquine. | Hydroxychloroquine now used.

Question 38

What drug can cause tears to turn red?

Answer 38

Rifampacin

Question 39

What does amiodarone cause in the eye?

Answer 39

Corneal verticullata | Looks like a whirl of spindle like cream lines in the pupil