Anti-glaucoma drugs

Question 1

What is dependent on how glaucoma is treated?

Answer 1

The age of onset and the rate of progression

Question 2

What is a huge risk factor of glaucoma?

Answer 2

Ocular hyper tension (they have a raised IOP but normal disc and fields)

Question 3

In a forest plot, what does the vertical line down the middle indicate?

Answer 3

Line of no difference

Question 4

Is there evidence to suggest that if you treat patients with ocular hypertension then you reduce the odds of visual field progression?

Answer 4

Yes- A meta analysis shows a 38% reduction in odds

Question 5

What is latanoprost?

Answer 5

A prostaglandin which lowers IOP in treating px with open angle glaucoma

Question 6

Is there a target IOP for glaucoma/ at risk glaucoma pxs?

Answer 6

No- there is not a single target, it is individually taking into account baseline iop, age of onset and determining what will cause slowest rate of progression

Question 7

On average what percentage of mmHg is the target IOP we try to reduce the IOP by?

Answer 7

20-35%–> 5-7mmHg

Question 8

What factors are taken to determine the target IOP?

Answer 8

• Rate of progression
• Early onset glaucoma
• Long life expectancy
• Late presenting glaucoma
• Status of other eye

Question 9

What is the drug of first choice for glaucoma treatment?

Answer 9

Prostaglandins

Question 10

If the first line treatment of prostaglandins are well tolerated and effective on lowering IOPs, then what happens next?

Answer 10

Px maintained on therapy, evaluated periodically to assess vision loss, optic disc status, IOPs and quality of life

Question 11

If the first line treatment of prostaglandins is not effective in lowering IOPs then what happens?

Answer 11

Substitute for a second drug or additionally a second drug is added or other therapeutic options are considered

Question 12

How does the LiGHT trial work in order to lower IOPs?

Answer 12

Laser trabecular plasticity- the laser is directed at the trabecular mesh work to open it up and lower resistance to outflow for primary open angle glaucoma

Question 13

What was significant about the LiGHT trial?

Answer 13

It could be more cost effective first-line open angle glaucoma and ocular hypertension treatment in lowering IOPs

Question 14

Are majority of drugs used to treatment glaucoma topical or systemic?

Answer 14

Topical

Question 15

Name the five classes of topical drugs

Answer 15

1) Prostaglandins
2) Beta receptor antagonists
3) Alpha 2 receptor agonists
4) Carbonic anhydrase inhibitors
5) Cholingeric agonists

Question 16

Which of the five classes of topical drugs is less widely used?

Answer 16

Cholingeric agonists

Question 17

Give an example of a cholingeric agonist?

Answer 17

Pilocarpine

Question 18

Give an example of a beta blocker anatagonist that was used in 1978

Answer 18

Timolol

Question 19

Give an example of a topical carbonic anhydrase inhibitor?

Answer 19

Dorzolamide

Question 20

What is the first prostaglandin to be used?

Answer 20

Latanoprost

Question 21

What is the mechanism of action of topical drugs? (3 ways)

Answer 21

• Reduce aqueous production
• Increase outflow through trabecular meshwork
• Increase uveoscleral flow

Question 22

Which class of drugs reduce aqueous production?

Answer 22

Alpha agonists, beta blockers and carbonic anhydrase inhibitors

Question 23

Which class of drugs increase outflow through trabecular meshwork?

Answer 23

Cholingerics

Question 24

Which class of drug increase uveoscleral flow?

Answer 24

Prostaglandins

Question 25

In which type of glaucoma would drugs be issues systemically and which drugs would be issues?

Answer 25

Acute angle closure Carbonic anhydrase inhibitors Osmotic agents

Question 26

Give an example of an carbonic anhydrase inhibitor

Answer 26

Acetazolamide (Diamox)

Question 27

Give an example of an osmotic agent

Answer 27

Glycerol, mannitol

Question 28

Before prescribing any new eye drop for glaucoma, what four things must you consider ?

Answer 28

- General medical history (factors which may increase risk of someone developing adverse effects) - Drug history (any interactions) - History of topical allergy - Can the px use eye drops (memory and dexterity)

Question 29

What four points must you consider when CHOOSING a drug?

Answer 29

- Efficacy (in lowering IOP) - Safety (which is the most appropriate drug fo this px) - Compliance (ensuring the px is taking the medication) - Cost

Question 30

Name the order high to lowest efficacy of glaucoma drugs

Answer 30

Prostaglandins agonists, beta blocker antagonists, alpha 2 agonists, cholingeric agonists, carnbonic anhydrase inhibitors

Question 31

What do the prostaglandin drugs end in?

Answer 31

Prost

Question 32

Name four prostaglandins

Answer 32

Latanoprost and travoprost and tafluprost and bimatoprost (prostamide)

Question 33

What is the trade name of latanoprost

Answer 33

Xalatan

Question 34

What is a side effect of prostaglandins?

Answer 34

Conjunctival hyperaemia (latanoprost is least likely for this to happen) Darkening, thickening and lengthening of eye lashes Increased iris pigmentation (affects px with light brown/ hazel eyes- not really the other colours)

Question 34

Name three beta-antagonist

Answer 34

Timolol maleate (non-selective) , betaxolol (selective) and levobunolol

Question 35

What is a side effect of beta- antagonists and why?

Answer 35

Can cause bronchoconstrition especially in patients with obstructive airways disease or asthma - because lungs have beta 2 receptors and stimulating or blocking these receptors causes bronchoconstriction

Question 36

What dosage of timolol is normally prescribed with a prostaglandin or carbonic anhydrase inhibitor?

Answer 36

Timolol 0.5%

Question 37

What conditions normally co-exist with glaucoma?

Answer 37

Airways disease- SO IMPORTANT TO MENTION THIS IN HISTORY

Question 38

Why is excluding airway disease so important when prescribing beta blockers when taking history?

Answer 38

It can cause bronchoconstriction and there is a relationship between usage of topical beta antagonists and new use/ increased use of bronchodilators

Question 39

What must you ask about/ do before prescribing beta antagonsits? *there are five

Answer 39

- Ask about COAD (chronic obstructive airways disease)/ SOBOE (shortness of breath on exertion)/ inhaler usage -Check peak flow - Check pulse - Consider drug interactions - Recheck peak flow one month after starting treatment

Question 40

What are the two alpha agonists for glaucoma treatment?

Answer 40

Brimonidine and apraclonidine

Question 41

How does briminodine work to reduce IOPs?

Answer 41

Increases uveoscleral outflow and reduce aqueous production

Question 42

When is apraclonidine used?

Answer 42

For post-operative management as a short term therapy to lower IOPs

Question 43

What are side effects of alpha agonists?

Answer 43

- High incidence of ocular side effects (e.g follicular conjunctivitis) - High incidence of systemic side effects such as hypotension, dry mouth, headache, anxiety, depression

Question 44

Name two topical carbonic anhydrase inhibitors

Answer 44

Dorzolamide and brinzolamide

Question 45

What are carbonic anhydrase inhibitors normally combined with?

Answer 45

Beta blockers

Question 46

What is an example of an oral carbonic anhydrase inhibitors?

Answer 46

Acetazolamide

Question 47

What are side effects of TOPICAL carbonic anhydrase inhibitors?

Answer 47

-Metallic taste - Rashes - Polyuria (excessive urination) - Irritation - Blurred vision

Question 48

What are side effects of ORAL carbonic anhydrase inhibitors?

Answer 48

- Allergy - Hypokalemia - Polyuria - Acidesis - Depression - Parethesia - Kidney stones - Blood dyscrasia

Question 49

Why is cholingergic not used?

Answer 49

Not cost effective and causes misosis, myopia, symblepharon, post synechiae, RD, confusion, vomiting, nausea

Question 50

What are six points that may influence compliance?

Answer 50

- Simplicity of regime - Memory - Manual dexterity - Understanding of disease - Topical side effects - Systemic side effects

Question 51

Why is cost important to consider?

Answer 51

We want to minimise cost to NHS

Question 52

If a patient needs more that two drops, then what are other options?

Answer 52

Selective laser trabeculaplastuy and trabeculemtory