Ocular Pharmacology Flashcards Preview

Pharmacology Fall 2016 > Ocular Pharmacology > Flashcards

Flashcards in Ocular Pharmacology Deck (89)
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1
Q

What is uveitis?

A

Inflammation of the uvea, iris, and ciliary body

2
Q

Is the epithelium of the cornea hydrophobic or hydrophilic?

A

Hydrophobic

3
Q

Is the endothelium of the cornea hydrophobic or hydrophilic?

A

Hydrophobic

4
Q

Is the stroma of the cornea hydrophobic or hydrophilic?

A

Hydrophilic

5
Q

Would an oil-based medication more easily penetrate the corneal epithelium or stroma?

A

Epithelium

6
Q

Would a water-based medication more easily penetrate the corneal endothelium or stroma?

A

Stroma

7
Q

When suspicious of a corneal ulcer, you would use a fluorescing stain toe identify the ulcer. Which layer of the cornea does this stain adhere to?

A

Stroma

8
Q

What are the 2 possible ways of drug absorption when topically administered?

A
  1. Penetration of the cornea

2. Systemic absorption through the conjunctiva and the nasolacrimal system

9
Q

Higher drug ____ or higher ____ of treatment can be used in order to increase the drug concentration in a treated tissue?

A

Higher drug CONCENTRATION or higher FREQUENCY of treatment can be used in order to increase the drug concentration in a treated tissue.

10
Q

Wait at least ___ minutes between different eye drops.

A

5 minutes

11
Q

Which MUST be shook well prior to application, an ophthalmic solution or suspension?

A

Suspension

12
Q

Which is more stable, ophthalmic drops or ointment?

A

Ophthalmic ointment

13
Q

Explain the penetration of subconjunctival injections.

A

Bypass the conjunctival and corneal barriers for direct scleral absorption

14
Q

What are the indications for subconjunctival injection?

A
  1. Bolus of medication for animals not permitting repeated topical application (Ex: wildlife, aggressive animal)
  2. For water-soluble drugs that would penetrate the cornea poorly
  3. For long-acting drugs
  4. To confine a drug’s effect to the eye
15
Q

Again, what are the indications for subconjunctival injections?

A
  1. For long-acting drugs
  2. For water-soluble drugs (unable to penetrate the cornea)
  3. To confine a drug’s effect to the eye
  4. For animals that will not permit repeated topical administration
16
Q

True or False: Systemically administered drugs have no effect on the anterior or vitreous chambers of the eye.

A

FALSE - systemic drugs do have an effect on these chambers.

17
Q

True or Falase: Most antibiotics penetrate the cornea well.

A

FALSE - most antibiotics have poor corneal penetration.

18
Q

Name the 3 polypeptide ocular drugs.

A
  1. Polymyxin B
  2. Gramicidin
  3. Bacitracin
19
Q

Are the polypeptides bacteriostatic or bactericidal?

A

Bactericidal

20
Q

Describe the spectrum of the polypeptides.

A

Broad spectrum

21
Q

True or False: The polypeptides can be administered topically, subconjunctivally, or systemically.

A

FALSE - the polypeptides are toxic when administered subconjunctivally or systemically. The polypeptides should only be used topically.

22
Q

Name 3 aminoglycosides used in ocular pharmacology.

A
  1. Gentamicin
  2. Tobramycin
  3. Amikacin
23
Q

Describe the spectrum of the aminoglycosides.

A

Broad spectrum

24
Q

Are the aminoglycosides bactericidal or bacteriostatic?

A

Bactericidal

25
Q

True or False: These aminoglycosides can be used systemically.

A

FALSE - aminoglycosides are toxic when used systemically.

26
Q

Which of the following is the most effective aminoglycoside, tobramycin or gentamicin?

A

Tobramycin

27
Q

Which of the following is least epitheliotoxic, tobramycin or gentamicin?

A

Tobramycin

28
Q

What is the most commonly used quinolone in ocular pharmacology?

A

Ofloxacin

29
Q

Describe the spectrum of the quinolones.

A

Broad spectrum (limited against anaerobes)

30
Q

Which antibiotic is effective against resistant staphylococcus?

A

Cephalosporins: Cefazolin

31
Q

The cephalosporin cefazolin is used mainly for what type of ocular infections?

A

Staph and strep infections

32
Q

True or False: The cephalosporin cefazolin easily penetrates the cornea.

A

FALSE - cefazolin has LOW corneal permeability.

33
Q

Which of the following are the tetracyclines, antibacterial, anti-inflammatory, anti-protozoal, anti-protease.

A
  1. Antibacterial
  2. Anti-inflammatory
  3. Anti-protease
34
Q

Are the tetras bacteriostatic or bactericidal?

A

Bacteriostatic

35
Q

The tetras are effective against ____ and ____.

A
  1. Mycoplasma

2. Chlamydophila (mainly in kittens)

36
Q

What is the only ophthalmic preparation of tetracycline?

A

Ointment

37
Q

Which fungal organism is miconazole effective against?

A

Aspergillus

38
Q

True or False: Miconazole has poor penetration of the cornea.

A

TRUE

39
Q

Which 2 fungal species is voriconazole effective against?

A
  1. Fusarium

2. Aspergillus

40
Q

True or False: Voriconazole has good penetration of the cornea.

A

TRUE

41
Q

What type of antivirals are currently the main antivirals used in veterinary ophthalmology?

A

Nucleoside analogs

42
Q

Nucleoside analogs are most frequently used to treat which virus?

A

Feline herpesvirus

43
Q

Nucleoside analogs are virostatic or virocidal?

A

Virostatic

44
Q

What is the administration protocol for Idoxuridine?

A

Every 2 hours for 2 days then 4-6 x/day for 3-4 weeks

45
Q

Which of the following is not effective against feline herpesvirus: Nucleoside analogs, Cidofovir, Acyclovir.

A

Acyclovir

46
Q

Which dose of Famciclovir has been reported to have a positive clinical effect?

A

90 mg/kg every 12 hours

47
Q

How does L-lysine interfere with viral replication?

A

Ties up arginine so it is not available for viral replication

48
Q

What can you use as a life-long food additive for chronic recurring feline herpesvirus infections?

A

L-lysine

49
Q

What is the administration protocol of L-lysine in PREVENTION of feline herpesvirus?

A

250-500 mg/cat every 24 hours

50
Q

What is the administration protocol of L-lysine in TREATMENT of feline herpesvirus?

A

250-500 mg/cat every 12 hours

51
Q

Do NOT use topical steroids on an eye with what?

A

Ulcerative keratitis

52
Q

Corticosteroids decrease the release of ____ from injured cell membranes.

A

Arachidonic acid

53
Q

Corticosteroids block degranulation of what 3 cell types?

A
  1. Neutrophils
  2. Mast cells
  3. Basal cells
54
Q

Corticosteroids prevent release of histamine, ____, and ____.

A
  1. Proteases

2. Bradykinin

55
Q

Corticosteroids increase or decrease capillary permeability?

A

Decrease

56
Q

Corticosteroids increase or decrease vasodilation?

A

Decrease

57
Q

Corticosteroids increase or decrease neovascularization?

A

Decrease

58
Q

What are the 3 general indications for corticosteroid use?

A
  1. Allergies
  2. Hypersensitivities
  3. Immune-mediated diseases
59
Q

How do corticosteroids affect fibroblast responses?

A

Inhibit fibroblast responses

60
Q

How do corticosteroids affect epithelial regeneration?

A

Interfere with epithelial regeneration

61
Q

How do corticosteroids affect collagen?

A

They potentiate proteinases that break down collagen

62
Q

What affect do corticosteroids have on intraocular pressure?

A

Increase intraocular pressure

63
Q

What affect do corticosteroids have on corneal epithelium and stroma?

A

Cause degeneration with long term use

64
Q

True or False: Just like in the human being, corticosteroids cause cataracts in animals.

A

FALSE - corticosteroids do NOT cause cataracts in animals.

65
Q

True of False: Corticosteroid can facilitate viral infections in prolonged use.

A

FALSE - corticosteroids can facilitate FUNGAL infections in prolonged use.

66
Q

Corticosteroids should be avoiding with metabolic diseases, especially ____ in small animals.

A

Diabetes

67
Q

Which of the following topical corticosteroids has the best corneal penetration: acetate, alcohol, or phosphate?

A

Acetate

68
Q

What would you use for intraocular inflammation?

A

Prednisolone acetate

69
Q

What would you use for extraocular inflammation?

A

Dexamethasone sodium phosphate

70
Q

Which corticosteroid is systemically used in small animals?

A

Prednisone or prednisolone

71
Q

Which corticosteroid is systemically used in horses?

A

Dexamethasone

72
Q

Which is preferred in exotic animals, steroids or NSAIDs?

A

NSAIDs

73
Q

How do NSAIDs work?

A

Prevent the formation of prostaglandins from arachidonic acid

74
Q

What are the primary mediators of ocular inflammation?

A

Prostaglandins

75
Q

What NSAID can be used in horses to treat SCC?

A

Piroxicam

76
Q

What are the 2 most common treatments for KCS to date?

A
  1. Tacrolimus

2. Cyclosporin (Optimmune)

77
Q

What affect do Tacrolimus and Cyclosporin have on tear production?

A

Stimulate tear production

78
Q

What are serum, N-acetylcysteine, EDTA, and tetracyclines?

A

Anti-proteases

79
Q

How do carbonic anhydrase inhibitors work?

A

Block the carbonic anhydrase enzyme, decreasing aqueous humor production

80
Q

For what condition would you use carbonic anhydrase inhibitors?

A

Glaucoma

81
Q

How do prostaglandin anaglogs decrease intraocular pressure?

A

By increasing uveoscleral outflow

82
Q

What are Latanoprost and Travoprost?

A

Prostaglandin analogues

83
Q

Which of the following is most cost effective, Latanoprost or Travoprost?

A

Latanoprost

84
Q

How are beta-adrenergic blockers anti-glaucoma?

A

Decrease aqueous humor production

They do this by blocking beta receptors on the ciliary epithelium

85
Q

What is the adverse effect of using a beta blocker?

A

Bradycardia

86
Q

True or False: Beta blockers can be used alone in the treatment of glaucoma.

A

FALSE - Beta blockers are not adequate in treating glaucoma when used alone. They are preferably used in combination with a carbonic anhydrase inhibitor.

87
Q

Osmotic diuresis can be used to lower intraocular pressure. What is the mechanism of this?

A

Shrinks the vitreous of the eye

88
Q

What is an example of a drug that can cause osmotic diuresis and shrinkage of the vitreous by association?

A

Mannitol

89
Q

In what patients would Mannitol be contraindicated?

A

Renal disease patients