Pharmacology Flashcards
(90 cards)
1
Q
Methods of ophthalmologic medication administration
A
- Topical
- Subconjunctival
- Systemic
- Intraocular
- Retrobulbar
2
Q
Factors that affect penetration into the eye
A
Solubility, Size, and Concentration
3
Q
Types of vehicles of topical medication
A
Drops - divebomb
Ointment - don’t go uphill
4
Q
Properties of vehicles
A
pH, tonicity, and preservatives
5
Q
Fate of drugs after topical administration
A
- from eye down nasolacrimal duct, possible systemic absorption.
- can be absorbed across conjunctival vasculature, and also possibly systemic absorption
- The hope is that most drugs for intraocular will pass through the cornea and into the anterior chamber.
6
Q
What is the most common way to treat the eye in veterinary medicine?
A
Topical administration via a periodic dosing
7
Q
What animals benefit most from lavage systems?
A
Horses especially but large animals in general
8
Q
Indication for topical administration?
A
Anterior chamber and cornea and surface level stuff. Not as reliable to get to posterior chamber or anywhere else
9
Q
Indication for subconjunctival administration?
A
bypasses conjunctival epithelium and allows absorption through episcleral vessels.
Longer duration
10
Q
Indication for subconjunctival administration?
A
- to increase drug level locally
2. when topical is inappropriate (large number of cattle)
11
Q
Problems associated with subconjunctival adminstration?
A
- irritating
- risk of puncturing the eye with needle
- status of the eye may change (non-ulcerated eye may become ulcerate)
- drugs leak back through the conjunctival epithelium into the precorneal tear film
12
Q
Indication for systemic administration?
A
- only way to treat the choroid, retina and optic nerve
2. can be used to treat adnexa and other parts (lid, conjunctiva, sclera, cornea
13
Q
When would systemic not be indicated over other methods?
A
Local disease
14
Q
Indication for intraocular administration?
A
- intraocular surgery (flushing solutions, manipulate the pupil, break down fibrin clots, …)
- treat Endophthalmitis, Equine Recurrent Uveitis
- treat Absolute Glaucoma (gentamicin)
- suprachoroidal implants for horses (ERU)
15
Q
Indication for retrobulbar administration?
A
- local anesthetics for standing surgery in Large Animals
16
Q
Indication for retrobulbar administration?
A
- local anesthetics for standing surgery in Large Animals
17
Q
Indication for retrobulbar administration?
A
- local anesthetics for standing surgery in Large Animals
18
Q
What’s in triple antibiotic topical?
A
Neo-Poly-Bac (ointment) or Neo-Gram-Bac (drops)
19
Q
What does each do in Neo-Poly-Bac and Neo-Poly-Gram?
A
Neomycin (aminoglycoside) good for G-
Polymyxin B good for G- and Pseudomonas
Bacitracin good for G+ (ointment)
Gramicidin good for G+ (drop)
20
Q
What does each do in Neo-Poly-Bac and Neo-Poly-Gram?
A
Neomycin (aminoglycoside) good for G-
Polymyxin B good for G- and Pseudomonas
Bacitracin good for G+ (ointment)
Gramicidin good for G+ (drop)
21
Q
Common topical drugs
A
- Triple Abx ointment and drop
- Chloramphenicol
- Gentamicin
- Tetracycline
- Fluoroquinolones
22
Q
What’s good about chloramphenicol?
A
Dr. Pickett’s fav. drug!
Broad spec – G+ and G- and ricketsial and chlamydia
Penetrates intact cornea well! so, good for INTRAOCULAR as well as stromal abscesses in horses
23
Q
What’s bad about chloramphenicol?
A
Irreversible Aplastic Anemia in Humans
Banned in Food Animals
24
Q
What’s bad about triple antibiotic?
A
hypersensitivities, not overly common though
25
What's good about Gentamicin?
G- spec and gets Pseudomonas
some G+, definitely staph but NOT strep
inexpensive as drop and as ointment
26
What's good about tetracycline?
drug of choice for Chlamydia and Rickettsials (gets intracellular)
have anti-proteolytic enzyme activity
27
What's bad about tetracycline?
do NOT use for Bacterial Ulcerative Keratitis because of RESISTANCE
28
What's good about fluoroquinolones?
BIG GUNS!!! Super Broad Spectrum, Penetrate well
Ciprofloxacin is expensive (humans)
Oflaxacin is far less expensive (vets)
29
What's bad about fluoroquinolones?
Reserve drug so don't use until you have to
| No off label in food animals I think
30
What's bad about fluoroquinolones?
Reserve drug so don't use until you have to
| No off label in food animals I think
31
What are the 8 antiviral medications?
1. Idoxuridine
2. Trifluorothymidine
3. Vidarabine
4. Cidofovir
5. Famcyclovir
6. L-Lysine
7. Interferon
8. Dilute Betadine solution (1:10 or 1:20)
32
What is idoxuridine?
Herplex anti-viral drops
33
What is trifluorothymidine?
Viroptic anti-viral is expensive and best anti-viral around
34
What is Vidarabine?
Vira-A anti-viral ointment, less expensive compared to others
35
What is cidofovir?
new topical anti-viral, well tolerated by Cats, can be used BID as opposed to q4-6hrs so far more manageable
36
What is famcyclovir?
Famvir anti-viral used for Feline Herpes Keratoconjunctivits.
Has limited toxicity, is effective, and comes in tablets or solutions
37
What's L-lysine, other than an amino acid?
Feline Anti-viral that ties up Arginine during viral replication. Used long-term in cats, don't know if it actually does anything
38
What's interferon?
bodies natural anti-viral for one, but pharmacologically it is a Systemic. Can put on for a week then off for a week.
can be used for chronic herpes cats
39
What's dilute betadine?
anti-viral for Kittens with herpetic keratoconjunctivitis. It is an inexpensive BacterioSTATIC and ViroSTATIC treatment that's somewhat effective.
Since povidone iodine is unstable, it needs to be mixed up daily or even more often
40
What are anti-mycotic agents most commonly used for?
Fungal Keratitis in horses
41
What are the 3 main anti-mycotic agents and the 4 others and the 1 group of random shit we were given?
```
Main 3:
1. Pimaricin
2. Miconazole
3. SSD (Silver SulfaDiazene)
Other 4:
1. Povidone Iodine
2. Fluconazole
3. Itraconazole (Itraconazole, DMSO, and petrolatum
4. Voriconazole
Random shit: (Amphotericin B, Clotrimazole, Flucytosine, Ketoconazole, Thiabendazole)
```
42
What is Pimaricin?
Natamycin, only drug approved for human or animal use as an anti-fungal agent.
Broad spectrum!
Does NOT penetrate the cornea well.
43
What is Miconazole?
anti-fungal, penetrate cornea better than Natamycin/Pimaricin
44
What is silver sulfadiazene?
Burn cream, effective against many fungi and bacteria.
| Silver binds to cell wall of fungus and is fungiSTATIC
45
How is povidone iodine an anti-fungal?
full strength 10% or diluted to 1%, used to swab Ulcer beds
46
What is fluconazole?
ineffective against most fungi
47
What would the itraconazole concoction be used for?
Fungal Keratitis in horses
48
What is voriconazole?
3rd Gen Azole, Topical, Broad spectrum and penetrates cornea well
49
What topical 2 NSAIDs are used?
1. Flurbiprofen (Ocufen)
| 2. Diclofenac (Voltaren)
50
What systemic 3 NSAIDs are used?
1. Aspirin
2. Phenylbutazone
3. Flunixin Meglumine (Banamine)
51
What are the 5 newer NSAIDs?
1. Ketoprofen
2. Carprofen
3. Meloxicam
4. Piroxicam
5. Etodolac
52
Are antihistamines and mast cell stabilizers used in vet med much?
Nope
53
How do steroidal anti-inflammatories work?
Inhibit arachadonic acid release and are immunosuppressive
54
Benefits of steroidal anti-inflammatories?
Anti-inflammatory effect on eye
| Reduce the Vascular Response (surface corneal neovascularization)
55
Adverse SE of ophthalmologic anti-inflammatory steroids.
1. Inhibit Ulcer healing
2. Potentiate Corneal proteolytic enzymes
3. long term use can cause lipid degeneration of cornea
4. topical and systemic uses can inhibit the pituitary-adreno-axis
56
Uses of steroid anti-inflammatories
1. Reduce inflammation post-op or non-pyogenic states
2. reduce inflammation of allergies or hypersensitivities
3. suppress auto-immune diseases
4. Reduce corneal neovascularization
5. reduce scar formation during healing
57
Contraindications for steroid use
Surface Ulceration!!!! ---> Inhibits ulcer healing
| Surface Ocular Infection
58
What is cyclosporine-A?
a calcineurin inhibitor, immunomodulating agent used as a topical for Keratoconjunctivitis Sicca and many types of keratitis such as Pannus in German Sherpherds
Newer drug is Tacrolimus
59
What is azathiaprine?
oral immunosuppressive agent used for cell-mediated hypersensitivity
used to treat uveitis and surface ocular disorders in dogs
Causes Bone marrow suppression and hepatotoxicity
60
What are the adverse side effects of azathiaprine?
Bone marrow suppressoin and hepatotoxicity
61
What is systemic cyclosporine-A used for?
immune mediated disease
62
What are the mydriatic/cycloplegic drugs?
1. Atropine
| 2. Tropicamide
63
What are the mydriatic non-clycloplegic drugs?
1. Phenylephrine
| 2. epinephrine
64
Atropine uses
treatment of anterior uveitis (stops pain of ciliary spasm in painful eye)
dilate pupil for surgery, for viewing around a cataract (paralyzes ciliary muscles)
to break down posterior synechia
65
Contraindications of atropine
dec. tear production so don't use in dry eyes
can trigger acute attack of angle closure glaucoma in predisposed dogs
can cause colic in horses (very rare)
66
Tropicamide uses
Diagnostic purposes, shorter duration makes ideal
67
Uses of phenylephrine and epinephrine
enhance maximal pupillary dilation for cataract surgery
| Diagnostic agent for Horner's
68
Miotic agents
```
Pilocarpine (direct acting)
Demecarium bromide (indirect acting)
```
69
Pilocarpine uses
treat primary angle closure gluacoma but used less frequently now since very irritating
70
Demecarium bromide uses
Treat primary closed angle glaucoma. It will somewhat open the iridocorneal angle and enhances flow of aqueous humor.
Can be prophylactic too (against same thing)
71
Antiglaucoma drugs
1. Carbonic anhydrase inhibitors
2. Beta blockers
3. Osmotic diuretics
4. Prostaglandin analogs
72
What's good about carbonic anhydrase inhibitors?
Decrease active production of aqueous humor from ciliary body epithelium
73
What's good about beta blockers?
decrease active production of aqueous humor
74
What's good about osmotic diuretics?
Used for emergency treatment of glaucoma, will help pull fluid from eye (and entire body)
75
What's good about prostaglandin analogs?
enhance uveoscleral outflow of aqueous humor
76
What are the CAI's we use in vetmed?
```
Systemic Pill form:
1. Methazolamide
2. Acetazolamide
Topical:
1. Dorzolamide
2. Brinzolamide
```
77
What beta-blockers do we use?
Timolol -- non-selective B1 and B2 blocker
78
What osmotic diuretics do we use?
1. Glycerin USP
| 2. Mannitol (better immediate effect)
79
What prostaglandin analogs do we use?
Latanoprost and Travoprost
| PGF-2alpha
80
What are cauterizing agents in ophtho?
ULCERS -- Horse with fungal ulcers, dogs with superficial erosion complex
Sterilize the eye
Enhance scar tissue formation
Enhance corneal neovascularization
81
What cauterizing agent does Dr. Pickett use?
Betadine, straight out of the bottle
82
What are anti-collagenase agents?
inhibit proteolytic enzymes
83
Which anti-collagenase agents do we use?
1. Acetylcysteine (in many ulcer "mixes")
2. Serum (alpha macroglobulin from clumped platelets)
3. NaEDTA (zinc cation binding drug)
4. Dilute Betadine
5. Systemic Tetracycline
84
Are eyewashes and lubricants the same thing?
NO THEY ARE NOT
85
What is eyewash for?
cleanse debris from the surface of the eye
Saline, LRS, other cocktails
can actually dry the eye out after they evaporate
86
What is lubricant for?
artificial tears
87
What's up with topical anesthetics for the eye?
diagnostic utility, NEVER for therapy
88
What dyes and stains do we use?
Na Fluorescein and Rose Bengal
89
What is Fluorescein for?
Topical: Stains Ulcers and check patency of nasolacrimal duct
Systemically: evaluate retinal vessels and the choroidal vasculature using cobalt blue filters to excite the stain
90
What is Rose Bengal for?
a Vital stain. Stains Necrotic cells red.
Good for localizing dry spots on corneal surfaces.
Also diagnose herpes keratitis in Cats.
