Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ophthalmology > Ocular Pharmacology > Flashcards

Ocular Pharmacology Flashcards

1
Q

What is required of topical preparations?

A

Required to act on a surface = need corneal penetration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What drug class are good for corneal penetration?

A

Low molecular weight drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How is the cornea structured?

A

Lipid : water : lipid sandwich = epithelium is lipophilic/hydrophilic, stroma is lipophobic/hydrophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does the structure of the cornea affect where drugs can be absorbed?

A

Lipid soluble drugs penetrate the epithelium, water soluble drugs penetrate the stroma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is an example of a drug that crosses the cornea easily?

A

Chloramphenicol = has both lipophilic and hydrophilic properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What effect may the tear film have on drug penetration?

A

May impeded drug penetration (lipid layer)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does the structure of the cornea impact what drugs have limited absorption?

A

Hydrophilic drugs are limited by the epithelium, hydrophobic drugs are limited by the stroma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What properties do topical steroids need to have?

A

Need to be both hydrophobic and hydrophilic = chemical modification may be needed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are some ways that steroids can be modified?

A

Alcohol or acetate may be added to make steroid more hydrophobic, phosphate may be added to make steroid more hydrophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are some features of prednisolone acetate?

A

Hydrophobic, good penetration in uninflamed cornea, used post-operatively

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are some features of prednisolone phosphate?

A

Hydrophilic , poor penetration in uninflamed cornea, used for corneal disease or when low dose steroids are needed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the common uses of benzalkonium chloride?

A

Surfactant and antibacterial agent = commonly found in household cleaning products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How may corneal penetration be enhanced?

A

By adding benzalkonium as a preservative = disrupts lipid layer of tear film and aids penetration of some drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are some features of bimatoprost 0.03%?

A

Drug used to lower intra-ocular pressure in glaucoma, has benzalkonium concentration of 0.05 mg/ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the benzalkonium concentration in bimatoprost 0.01%?

A

0.2 mg/ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are some features of the systemic absorption of drugs?

A

Tears are pumped out of the lacrimal sac rapidly, excess gains systemic absorption at nasopharynx, limited by punctal occlusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are some routes of administration?

A

Subconjunctival, subtenons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the types of intra-ocular injection?

A

Intravitreal, intracameral

19
Q

What are some uses of ophthalmic drugs?

A

Treatment of infection, treatment of inflammation, treatment of glaucoma, diagnostic eye drops, intra-ocular injections, ocular toxicity

20
Q

What are some common anti-inflammatory agents used?

A

Steroids, topical NSAIDs, antihistamines, mast cell stabilisers

21
Q

What are the actions of steroids?

A

Suppress inflammation, allergy and immune response

22
Q

What are steroids commonly used topically for in the eye?

A

Post-operative cataracts, uveitis and to prevent corneal graft rejection

23
Q

What are the local effects of steroids?

A

Cataracts, glaucoma, exacerbation of viral infection

24
Q

What are some systemic effects of steroids?

A

Gastric ulceration, immunosuppression, osteoporosis, weight gain, diabetes

25
Q

What are some different strengths of steroids?

A

FML, predsol (prednisolone phosphate), betamethasone, dexamethasone/prednisolone acetate

26
Q

What are antihistamines and mast cell stabilisers used for?

A

Hayfever and allergic conjunctivitis

27
Q

What are NSAIDs mainly used for?

A

Pain relief (i.e post-refractive laser)

28
Q

What is glaucoma?

A

Group of diseases characterised by a progressive optic neuropathy resulting in field defects

29
Q

What is the only modifiable risk factor for glaucoma?

A

Raised intra-ocular pressure

30
Q

What are some features of glaucoma?

A

Usually asymptomatic, screened for by optometrist, chronic disease, usually slowly progressive, incidence increases with age

31
Q

What are some treatments for glaucoma?

A

Prostanoids = latanoprost
Beta blockers = timolol, betaxolol, levobunolol cartelol
Carbonic anhydrase inhibitors = topical (dorzolamide) or systemic (acetazolamide)
Alpha 2 adrenergic antagonists = brimonidine (contraindicated in children as it causes sleep apnoea)
Parasympathomimetic = pilocarpine
Cosopt = combo of dorzolamide and timolol

32
Q

What is the benefit of intravitreal delivery?

A

Delivers effective concentration of drug at the target site instantly

33
Q

What is an issue with intravitreal delivery?

A

Many drugs are toxic to the retina

34
Q

What is intravitreal delivery used for?

A

Delivery of antibiotics in endophthalmitis and intra-ocular steroids

35
Q

How does local anaesthetic work?

A

Blocks sodium channels and impedes nerve conduction

36
Q

What is local anaesthetic used for?

A

FB removal, tonometry (intra-ocular pressure measurement), corneal scraping, comfort, cataract surgery

37
Q

What is the most common diagnostic dye?

A

Fluorescein

38
Q

What is fluorescein used for?

A

Showing corneal abrasion and dendritic ulcers
Identifying leaks and nasolacrimal duct obstruction
Tonometry and angiography

39
Q

What are some examples of mydriatics?

A

Tropicamide, cyclopentolate

40
Q

What do mydriatics do?

A

Cause pupil dilation by blocking parasympathetic supply to iris = cause cycloplegia (stop lens from focusing)

41
Q

What are some side effects of mydriatics?

A

Blurring of vision, acute angle closure glaucoma

42
Q

What type of drug should never be used to treat herpetic keratitis?

A

Steroids

43
Q

What do sympathomimetics do?

A

Act on sympathetic system to cause pupil dilation

44
Q

What can some sympathomimetics cause?

A

Cycloplegia = some can (atropine) and some cannot (phenylephrine)

Ophthalmology (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions