Midterm 1 Flashcards
1
Q
Diagnostic drug/agent
A
Chemical used to facilitate an examination and/or diagnosis
2
Q
Therapeutic drug/agent
A
Chemical used to treat a disorder of the eye or vision
3
Q
Medical conditions to consider when prescribing medications
A
Renal/hepatic disease, cardiovascular disease, respiratory disease, thyroid disease, DM, CNS conditions, affective/mental health disorders, pregnancy
4
Q
Why do we ask patients about medications they are taking?
A
Concerned about drug-to-drug interactions (including OTC), drug allergies, and ocular side effects of those medications
5
Q
Local adverse reactions from TOPICAL Medications
A
Cutaneous, conjunctiva, cornea, intraocular pressure, crystalline lens, retina, macula edema, bulbar follicles, corneal verticillata, PSC, etc.
6
Q
Systemic adverse reactions from TOPICAL medications
A
Impact HR, respiration
7
Q
Ocular adverse effects from SYSTEMIC medication
A
Dry eye, corneal verticillata, PSC, retinal toxicity, optic neuropathy, papilledema, accommodation issues
8
Q
Special populations to consider
A
Pregnant/lactating patients, pediatric patients, geriatric patients
9
Q
Pregnancy category A
A
- adequate well-controlled studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy
- very few drugs fall in this category
10
Q
Pregnancy category B
A
- animal reproductive studies have failed to demonstrate a risk to the fetus, and there are no adequate human studies
- fair number of drugs in this category
11
Q
Pregnancy category C
A
animal reproductive studies have shown an adverse effect on the fetus and there are no adequate human studies; potential benefits may warrant use of the drug in pregnant women despite potential risks
12
Q
Pregnancy category D
A
- there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies
- potential benefits may warrant use of the drug in pregnant women despite potential risks
13
Q
Pregnancy category X
A
- studies in animals or humans have demonstrated fetal abnormalities and/or there is positive evidence of human fetal risk
- risks involved in the use of the drug in pregnant women clearly outweigh potential benefits
14
Q
Geriatric patient considerations when prescribing
A
- eyelid laxity may increase retention time and increase systemic absorption
- arthritis/tremor may make instillation of topical meds more difficult
- cognitive difficulties may lead to poor medication adherence
15
Q
Pediatric dosing: Young’s Rule formula
A
Age (years) / (Age + 12) X Adult dose = pediatric dose
16
Q
Pediatric dosing: Webster’s Rule
A
- based on age and the fact that children are heavier now
- (age + 1) / (age + 7) X adult dose
17
Q
Pediatric dosing: Clark’s rule***
A
- based on weight, making it more accurate
- weight in pounds / 150 X adult dose
18
Q
Properties of outer lipid layer of tear film
A
Readily washed away with irrigation and tearing; not very stable
19
Q
Properties of middle aqueous layer
A
- 95% of entire tear volume
- inherently unstable
20
Q
Properties of inner basal layer (mucoid)
A
- comprised of glycoproteins secreted by goblet cells
- very thin and hydrophilic
21
Q
What properties must a drug contain to penetrate the cornea?
A
A balance of hydrophilic and lipophilic properties to go between both the epithelium and stroma
22
Q
The epithelium can act as a depot/reservoir for ___ drugs
A
Lipophilic
23
Q
The stroma can act as a depot/reservoir for ___ drugs
A
Hydrophilic
24
Q
Properties of corneal epithelium
A
- squamous layer with zonula occludens/tight junctions
- resists penetration of hydrophilic drugs when intact
- when eroded –> increased penetration of hydrophilic drugs
25
Properties of corneal stroma
- 90% of corneal thickness
| - collagen fibrils occupy space and increase the path of diffusion of molecules
26
Properties of corneal endothelium
- monolayer of polygonal cells
- non-regenerative
- pumps its own weight in fluid from stroma to AC in 5 minutes
- NOT a reservoir for drugs
- contains tight junctions
27
Pigment granules in iris epithelium absorb ___ drugs
Lipophilic
28
Vascular endothelial cells in iris contain ___ junctions
Tight
29
When iris is inflamed, what happens to the blood-aqueous barrier?
It becomes compromised
30
Where are the tight junctions in the ciliary body?
- between non-pigment epithelial cells
- capillaries do not contain tight junctions
- some systemic drugs pass through ciliary body vasculature and diffuse into the iris
31
Retina is developed from ____ in utero
Neural tube wall
32
RPE contains ___ junctions
- tight
| - prevent movement of drugs from blood to retina/vitreous
33
___ drugs can pass more easily into the retina via retinal capillaries
Lipophilic
34
What systemic drugs can cause toxicity of the optic nerve?
- chloramphenicol
- ethambutol
- streptomycin
- digitalis (retrobulbar optic neuritis)
- Vitamin A (high concentrations can cause papilledema)
35
Properties of drug formulations that affect bioavailability
- preservatives
- vehicles
- ointment
- drug release systems
- soft contact lens
- collagen shield
- punctal plugs
36
How do surfactants in preservatives damage ocular surface?
- disrupt plasma membranes (dish soap on water)
- BAK is toxic to corneal epithelium, enhances ocular penetration
- Chlorhexidene doesn't alter corneal epithelium as much as BAK, and isn't used as often
37
How do mercurials in preservatives damage the ocular surface?
Thimerosal has a high rate of toxicity/poor tolerability, but not used often anymore
38
How do ionic buffering preservatives affect the ocular surface?
- better tolerability but only available in a few medications
- great for glaucoma due to long-term use of medications
39
What is a vehicle and what's its purpose in drugs?
- agents other than the active ingredient or preservative
- provide proper tonicity, pH, buffering, viscosity
- can be used to increase contact time, provide temporary lipid depot, moisturize/lubricate the cornea/ocular surface
40
Advantages of ophthalmic ointments
- antibiotics are more stable in ointments than in solutions
- 2X the contact time in a blinking eye
- 4X the contact time in a closed (patched) eye
41
Disadvantages of ophthalmic ointments
- blur
- difficult to administer
- more risk of trauma from tube
42
Advantages of ophthalmic solutions/suspensions
- easier to use
| - less impact on vision
43
Disadvantages of ophthalmic solutions/suspensions
- shorter ocular contact time
- imprecise/inconsistent delivery
- contamination of bottle
- suspensions MUST be shaken
- clogged dropper tip with suspensions
44
Tan cap color
Anti-infectives
45
Pink cap color
Anti-inflammatories/steroids
46
Red cap color
Mydriatics and cycloplegics
47
Grey cap color
Non-steroidal anti-inflammatories
48
Green cap color
Miotics
49
Yellow cap color
Beta-blockers
50
Dark blue cap color
Beta-blocker combinations
51
Purple cap color
Adrenergic agonists
52
Orange cap color
Carbonic anhydrase inhibitors
53
Aqua blue cap color
Prostaglandin analogs
54
"SM" (sub-micron) technology
- designed to adhere to the ocular surface and then penetrate key ocular tissues
- been using for about 20 years
55
"Ncell" technology
- enhances the ocular delivery of cyclosporine
- supposed to get through cornea faster
- micelles of hydrophobic core and hydrophilic shell
56
Microdose dispenser
- new technology will be approved within the next year (2022)
- 8 nanoliters of drug administered instead of 40 in a typical eyedropper
- patient can sit upright for administration
57
Nano-dropper
- replaces cap on commercially available eyedrop bottle
- financial benefit to the patient
- patient still has to tilt their head back
58
Intracameral injection
- injection into anterior chamber
- new glaucoma delivery system
- pellet that eventually dissolves and delivers medication for 3 months
59
Intravitreal injections
- antibacterial/fungal to treat endophthalmitis
- corticosteroid to treat posterior uveitis
- anti-VEGF therapy (Avastin, Lucentis, Eyelea) to treat wet AMD, proliferative diabetic retinopathy
60
Intravitreal implants
- antiviral (ganciclovir - VITRISERT) - first intravitreal implant for HIV patients
- corticosteroid (Retisert, Ozurdex, Yutiq)
61
Ozurdex (Dexamethasone)
- fully bio-erodible
- lasts approximately 6 months
- FDA approved for DME, macular edema from retinal vein occlusion, and chronic non-infectious posterior uveitis
62
Retisert (fluocinolone acetonide)
- intravitreal steroid implant
- FDA approved for treatment of chronic non-infectious uveitis
- lasts approximately 2.5-3 years
63
Yutiq (fluocinolone acetonide)
- intravitreal steroid micro-insert
- FDA approved for chronic non-infectious posterior uveitis
- non-bio-erodible
- insertion done in-office
64
Vitrisert
- Gangiclovir (antiviral)
| - used to treat infectious cytomegalovirus infection
65
What is included in the prescriber's information in a prescription?
Name, address, phone, license # (NPI), DEA #
66
What all is included in the anatomy of a prescription?
- prescriber's information
- date
- patient data
- superscription
- inscription
- subscription
- signa or signatura
- refill information
- prescriber's signature
67
What is included in the inscription?
- name of drug
- concentration/strength
- formulation (gel, ointment, solution, etc.)
68
What is included in the subscription?
- quantity of the drug the pharmacist should dispense
- brief - number of tabs/capsules, weight of container, volume of bottle, etc.
- usually preceded by the # sign
- Ex: Dispense #5ml
69
What is included in the signatura?
- instructions for use
- how to use (take, instill, apply, etc.)
- how much and how often to use
- Ex: Instill 1 drop in each eye twice daily
70
a.c. stands for
before meals
71
p.c. stands for
after meals
72
h.s. stands for
at bedtime (also qhs)
73
ut. dict stands for
as directed
74
Definition of controlled substances
Substances that may produce physical, psychological dependence (or both)
75
Schedule I drugs
- very high potential for abuse
- no approved medical use; no research use; cannot be prescribed
- Heroin, LSD
76
Schedule II drugs
- high potential for abuse
- strict limitations for medical use, must be electronically submitted, NO REFILLS allowed
- opioids such as morphine, codeine (with certain concentrations), oxycodone, hydrocodone, amphetamines, and cocaine
77
Schedule III drugs
- significant potential for abuse
- often used for pain management; must be e-Rx; NO REFILLS
- weaker opioids such as codeine, some amphetamine-like drugs
- ODs can prescribe
78
Schedule IV drugs
- less than III potential for abuse
- medical use is accepted; up to 5 refills in 6 months
- propoxyphene, diazepam, phenobarbital
79
Schedule V drugs
- less than IV potential for abuse
- often used for cough suppression or to treat diarrhea; up to 5 refills in 6 months
- cough syrups with codeine; antidiarrheal diphenoxylate
80
Americans are ___X more likely to be hospitalized by a prescription rather than by a car accident
10
81
Sympathetic pre-synaptic fibers are ___ and post-synaptic fibers are ___
Short; long
82
Parasympathetic pre-synaptic fibers are ___ and post-synaptic fibers are ___
Long; short
83
The sympathetic NT on the effector organ is?
Norepinephrine
84
The parasympathetic NT on the effector organ is?
Acetylcholine
85
Cholinergic innervation to the eye is the same as
Parasympathetic
86
Where does cholinergic innervation to the eye originate?
In the Edinger-Westphal nucleus
87
What structure does cholinergic innervation to the eye travel with?
CN III
88
Where does cholinergic innervation to the eye synapse?
In the ciliary ganglion
89
Where does the post-synaptic cholinergic innervation to the eye travel?
To the iris sphincter muscle and ciliary body via short ciliary nerves (cause pupil constriction)
90
What happens to the lens when the ciliary body contracts?
It moves towards the cornea
91
How is the lacrimal gland innervated?
Parasympathetically via CN VII/sphenopalatine ganglion/CN V
92
What is the pupil size primarily determined by?
Iris sphincter muscle tone
93
Cholinergic stimulation to the eye causes what?
Miosis, contraction of the ciliary body, and decrease in IOP ( --> more AH outflow)
94
Cholinergic agents are also known as
- miotics
- cholinergic agonists
- parasympathetic agonists
- parasympathomimetics
95
What are the two types of miotics?
- direct acting (which mimic Ach)
| - indirect acting (which are AchE inhibitors)
96
What are some direct acting miotics?
- pilocarpine
- carbachol
- civimeline (oral)
97
What is a reversible indirect acting miotic?
Edrophonium
98
What are the effects of miotics in the eye? (6)
- pupillary constriction
- spasm of accommodation
- decreased IOP
- narrowing/shallowing of the AC
- increased thickness of crystalline lens
- increased vascular permeability in iris blood vessels
98
What are systemic effects of miotics?
- salivation
- lacrimation
- urination
- defecation
- GI upset
- emesis
- bronchoconstriction
99
What are some irreversible indirect acting miotics?
- DFP
| - echothiophate
101
What are the ophthalmic uses of miotics? (6)
- diagnosis of some pupil abnormalities
- glaucoma treatment
- diagnosis of MG
- treatment of phthiriasis palpebrum (pubic lice on lashes, rare to use this way)
- treatment of dry eye in patients with aqueous deficiency
- presbyopia treatment (Vuity)
102
How to know if anisocoria is physiologic or abnormal?
If the anisocoria (difference) is greater in the light than in the dark, it's an abnormal cause of anisocoria
103
3 things to consider with abnormal anisocoria
- damage to efferent CN III fibers --> EMERGENCY!
- tonic pupil
- pharmacologic blockade
104
General guidelines for pharmacologic anisocoria evaluation (how to administer drops, tests, procedures to avoid, etc.)
- one drop of diagnostic agent in each eye; repeat after several minutes
- no anesthetic or tonometry (can alter drug penetration)
- if condition is bilateral, only instill in one eye (not common)
- maintain same ambient illumination before and after instillation
- eliminate accommodative stimulus and have patient look straight at distance
- IR photography can be very helpful
105
What is tonic pupil (Adie's pupil)?
- pupil with parasympathetic denervation
- typically unilateral
- often associated with virus or trauma
- women of 25-40 years of age, complain of photophobia
- often resolves after 2 years
- rare systemic association (zoster, giant cell arteritis, syphilis)
- benign, and kind of unexplainable
- constricts better to accommodative stimulus than to light
106
How to diagnose tonic pupil
- 0.125% pilocarpine:
- will not constrict a normal pupil (or very little)
- significant constriction of tonic pupil due to the upregulation of receptors and the eye becoming super sensitive to parasympathetic stimulation
107
Describe CN III dilated pupil
- considered a neurologic emergency (likely aneurysm of posterior communicating artery until proven otherwise!)
- rare to find ONLY pupil involvement, usually oculomotor palsy (ptosis, motility, etc.)
108
Steps of pharmacologic testing of CN III dilated pupil
- 0.125% pilocarpine to see if it's tonic
- if NO constriction then 0.5% - 1% pilocarpine
- CN III - prompt constriction
- pharmacologic blockade - NO constriction
109
What is likely happening in a CN III palsy that doesn't involve the pupil?
Likely not an aneurysm pressing on the nerve, as the pupil fibers are on the outside, likely ischemia to the nerve
110
Approach to one dilated pupil (anisocoria)
- evaluate lids and motility
- check light response and near response - is there dissociation?
- check for vermiform (wiggly)/sector paresis of iris sphincter at slit lamp (tonic)
- pharmacologic testing:
1) dilute pilocarpine (0.125%)
2) normal strength pilocarpine (0.5 - 1%)
3) if no constriction to either --> pharmacologic
* *THERE WILL BE MORE THAN 1 QUESTION ON EXAM ON PUPIL PROBLEMS**
111
What is the mechanism of action of miotics in open angle glaucoma and what drugs are used to achieve this?
- stimulate longitudinal muscle of the ciliary body
- pull on scleral spur
- opens spaces in trabecular meshwork
- result in increased aqueous outflow through trabecular meshwork
- drugs used: pilocarpine and rarely carbachol, which is much stronger
112
What is the conventional pathway of AH out of the anterior chamber?
60-80% of AH leaves through TM --> Schlemm's canal --> episcleral veins
113
How is pilocarpine used in glaucoma therapy (concentrations, dosing, etc.)?
- decreased effect in darkly pigmented irises due to pigment binding
- available 0.5% - 10% solution, 4% gel
- dosing QID (solution), nightly (gel)
- not used frequently due to high incidence of local (in and around the eye) side effects and frequent dosing
114
Contraindications of pilocarpine (6)
- young age due to accommodative spasm and brow ache
- cataract (visual axis)
- retinal disease (can negate effects of dilation drops that have to be used for annual eye exam)
- uveitis (vascular permeability)
- neovascular glaucoma (vascular permeability)
- asthma
115
What is happening to the eye during pupillary block glaucoma?
In the mid-dilated position, the pupil pushes right up against the lens and AH can't pass through --> iris bulges forward --> no access to the angle --> IOP goes up to 60-70 mmHg
116
How is pilocarpine used in treatment of pupillary block?
- small concentrations of pilocarpine make the pupil smaller and move it off the lens
- keep patient on pilocarpine until they are able to have iridotomy done
117
Additional side effects of irreversible AchE inhibitors
- SLUDGE
- iris cysts
- anterior subcapsular cataracts
- retinal detachment (a little bit stronger correlation)
- acute angle closure glaucoma
- uveitis
- follicular conjunctivitis
- decreased rate of hydrolysis of succinylcholine can lead to respiratory paralysis (used for anesthesia)
118
What is the drug of choice for the diagnosis of MG?
Edrophonium
119
What is myasthenia gravis?
- disease that affects the neuromuscular junction
- antibodies to acetylcholine receptors in the motor end plate of SKELETAL MUSCLE - effectively reduces the number of Ach receptors
- characterized by muscle weakness and fatigue as the day goes on
- ocular involvement in 90% of patients; only affects skeletal muscle (no effect on pupil or ciliary muscle)
- ptosis, EOM involvement that is variable within minutes, hours, days or weeks
120
Diagnosis of myasthenia gravis includes
- lid fatigue --> have patient stare in up gaze, preferably in the afternoon
- lid twitch sign (cogan's sign)
- enhanced ptosis
- variability in measuring tropia/phoria
- tensilon/enlon test: positive test = diagnosis; negative test = may or may not have MG
- Ach antibodies in 1/3 of patients
- have to do tensilon test while patient is having symptoms
- typically done in the hospital because it can be very risky
121
Treatment of phthiriasis palpebarum
- typically done by removing nits, cutting lashes at the base and smothering with bland petrolatum
- can use acetylcholinesterase but the SE limit usefulness (nobody really does this)
122
Miotics in dry eye treatment (drug name, dose, side effects, etc.)
- Salagen (pilocarpine 5 mg) indicated for treatment of dry mouth due to radiotherapy of head/neck or Sjogren's syndrome
- off-label for dry eye
- dose 5 mg orally TID-QID
- side effects include LOTS of sweating and other expected cholinergic SE
- Evoxac (civimeline) indicated for treatment of dry mouth from Sjogren's
- off-label for dry eye
- dose 30 mg orally TID
- side effects same as Salagen
123
Vuity is used to treat
Presbyopia
124
How does Vuity work?
Improves near vision by increasing the depth of focus by creating a small pupil
125
What are some side effects of Vuity that are seen in >5% of study patients?
- headache due to accommodative spasm
| - conjunctival hyperemia, likely from vascular permeability
126
What are some side effects of Vuity seen in 1-5% of study patients?
- blurred vision (inducing myopia)
- eye pain
- eye irritation
- impaired vision
- lacrimation
127
How do anticholinergic (cycloplegic) agents work?
- inhibit the actions of acetylcholine to cause mydriasis, cycloplegia, and potentially elevated IOP
- affect autonomic effector sites
- affect some smooth muscle sites
128
Cycloplegic agents are also known as
- anti-muscarinics
- cholinergic antagonists
- anticholinergics
- mydriatics (bad term)
- cycloplegics
- mydriatic-cycloplegics
129
What are some cholinergic antagonists?
- atropine
- homatropine
- scopolamine
- cyclopentolate
- tropicamide
130
What is the most potent mydriatic and cycloplegic agent available?
Atropine
131
How long does mydriasis last after administering atropine?
Up to 10 days
132
How long does cycloplegia last after administering atropine?
Up to 12 days
133
How do dark irises affect the effects of atropine?
Pigment binding causes mydriasis and cycloplegia to have a delayed onset and longer duration of action
134
At what time is maximum mydriasis achieved when using atropine?
30-40 minutes unless it's a very dark eye
135
At what time is maximum cycloplegia achieved when using atropine?
- 60-180 minutes
| - because of this, atropine isn't very practical clinically for a refraction
136
Clinical uses of atropine
- cycloplegic refraction if you want to find the most plus possible
- treatment of anterior uveitis/hyphema
- treatment of myopia
- treatment of amblyopia
137
Under what special circumstances might you use atropine for cycloplegic refraction?
- small children with active accommodation and suspected latent hyperopia or accommodative ET
- would use nasolacrimal occlusion to reduce systemic SE
- hand washing for parent instilling the drops
138
What can atropine be used to treat? (besides amblyopia and myopia, 3)
- anterior uveitis or really any inflammation of the ciliary body - relieves pain associated with inflammation and ciliary body spasm
- prevention of posterior synechiae
- may decrease permeability of inflamed vessels
139
What is the mechanism of action of atropine when treating myopia?
- CB is at rest and accommodation is relaxed
| - use of very low dose showed significant effect in reducing myopia progression
140
How is atropine used to treat amblyopia?
- alternative to patching
- may be combined with overcorrection or undercorrection of the better eye (VA in amblyopic eye must be better than VA in non-amblyopic eye)
- careful to not induce amblyopia in the other eye
141
Ocular side effects of atropine
- allergic dermatitis
- risk of angle closure, though this is remote/negligible if angles are open
- increased IOP in open angles, but rare
- ocular side effects may occur with systemic use
- systemic side effects may occur with topical use
- when using low concentrations, these risks are minimal
142
Systemic side effects of atropine
- dose dependent
- low: more likely to produce peripheral effects such as dry mouth, flushing of face, and inhibition of sweating
- increasing dose: central (CNS) effects such as convulsions, cognitive impairment, delirium, and death but rare
- use caution in lightly pigmented individuals, young children and down's syndrome
143
How to treat overdose of atropine
- supportive if peripheral effects and physostigmine if central effects
144
Contraindications to atropine
- known hypersensitivity
- POAG, but not absolute
- caution in infants, small children and elderly
- down's syndrome
145
What is the potency of homatropine compared to atropine?
1/10 the potency of atropine
146
When is maximum mydriasis achieved with homatropine?
40 minutes
147
How long does mydriasis last with homatropine?
1-3 days
148
How long does cycloplegia last with homatropine?
Longer than cyclopentolate but not as strong as atropine or cyclopentolate
149
Clinical uses of homatropine
- not typically used for cycloplegic refraction because less hyperopia is uncovered
- primarily used to treat anterior uveitis
150
Contraindications of homatropine
- known hypersensitivity
- POAG, but not absolute
- caution in infants, small children and elderly
- down's syndrome
151
When does maximum mydriasis occur with scopolamine?
20 minutes
152
How long does mydriasis last with scopolamine?
2-8 days
153
When does maximum cycloplegia occur with scopolamine?
40 minutes
154
Clinical uses for scopolamine
- not first choice for cycloplegic refraction or treatment of anterior uveitis (but still effective for anterior uveitis)
- more CNS effects because it crosses the BBB
155
Side effects of scopolamine
- similar to atropine
- slightly higher CNS toxicity:
- restlessness
- confusion
- incoherence
- violence
- drowsiness
- vomiting
- urinary incontinence
156
Contraindications of scopolamine
same as atropine
157
Can mydriasis and cycloplegia result from hand to eye contact and from systemic absorption from transdermal scopolamine?
Yes
158
When does maximum mydriasis occur with cyclopentolate?
- white patients: 20-30 minutes
| - black patients: 30-60 minutes
159
When does maximum cycloplegia occur with cyclopentolate?
- 30-60 minutes
| - as early as 10 minutes in light color eyes
160
How long does cycloplegia last with cyclopentolate?
- about 24 hours
| - ALWAYS TELL THE PATIENT THIS
161
Clinical uses of cyclopentolate
- DO1C for cycloplegic refraction
- treatment of anterior uveitis
- mild cases
- people sensitive to atropine
- more frequent doses needed than atropine (tid to qid)
162
Ocular side effects of cyclopentolate
- stinging
- allergic reaction (rare)
- toxic keratitis with prolonged use
- IOP increase in POAG (less common than atropine)
- precipitation of angle closure in susceptible patients
163
Systemic side effects of cyclopentolate
- similar to atropine (more CNS)
- drowsiness, but also agitated
- restlessness
- memory loss
- visual hallucinations
- grand mal seizures reported but rare
- MORE common in children, and with 2%
164
Contraindications to cyclopentolate
> 0.5% solution may be contraindicated in patient profile similar to atropine contraindications
165
When does maximum mydriasis occur with tropicamide?
25-30 minutes
166
How long does mydriasis last with tropicamide?
6 hours, longer in dark irises
167
Is the mydriatic effect of tropicamide dose-related?
No
168
When does maximum cycloplegia occur with tropicamide?
30 minutes
169
Is the cycloplegic effect of tropicamide dose-related?
Yes
170
What cycloplegic drop has the greatest mydriasis effect at 30 minutes?
Tropicamide
171
Clinical uses of tropicamide
- ophthalmoscopy: less dependent of iris pigment; most commonly used with a sympathomimetic
- cycloplegic refraction in school-aged children without suspected high hyperopia or suspected latent/accommodative ET ("damp" refraction)
172
Side effects of tropicamide
- stinging
| - increased IOP in POAG
173
Contraindications of tropicamide
Narrow anterior chamber angles
174
Effects of adrenergic stimulation to the eye
- pupillary dilation
- widening of the palpebral fissure (Mueller's muscle)
- vasoconstriction
- decreased IOP, but we're unsure why
- inhibition of accommodation (very small amount)
175
What are some examples of topical adrenergic agonists?
- phenylephrine
- hydroxyamphetamine
- cocaine (diagnostic of Horner's)
- apraclonidine (glaucoma)
- brimonidine (glaucoma)
176
Pharmacology of phenylephrine
- direct-acting
- analogy of epinephrine
- acts primarily on alpha-1 receptors
- may cause minimal release of NE at terminals
177
Phenylephrine stimulates (3 things) and may cause what?
- iris dilator muscle
- conjunctival arteriole smooth muscle (blanches blood vessels)
- Mueller's muscle of the upper eyelid
- may cause decreased IOP
178
What are the common clinical uses of phenylephrine?
- pupillary dilation
| - breaking posterior synechiae
179
When is maximum mydriasis achieved with phenylephrine?
45-60 minutes
180
How much does phenylephrine affect accommodation?
very minimally (2D)
181
What concentration of phenylephrine do we use for DFE?
2.5%
182
What concentration of phenylephrine do we use for breaking posterior synechiae?
10%
183
Ocular side effects of phenylephrine
- transient pain, lacrimation, keratitis
- allergic dermatitis/conjunctivitis if used routinely
- release of pigment granules from iris
- rebound congestion with chronic use
184
Systemic side effects of phenylephrine (potential concern for DFE)
- possibly systemic hypertension, but not really conclusive
| - can punctal occlude if you're concerned
185
Patient populations likely to experience increased BP response to 10% phenylephrine
- neonates
- "insulin-dependent" DM
- idiopathic orthostatic hypotension
186
Other reported systemic side effects to 10% phenylephrine (6)
- occipital HA
- subarachnoid hemorrhage
- ventricular arrhythmia
- ruptured aneurysm
- tachycardia/reflex bradycardia
- blanching of skin
187
What medications can exacerbate systemic side effects of phenylephrine?
- atropine
- TCAs
- MAOIs
- guanethidine, reserpine, methyldopa
188
What is Horner's syndrome?
sympathetic paralysis or denervation
189
Signs of Horner's syndrome
- lid ptosis
- miosis
- anhidrosis of the face in some cases
190
Why does congenital Horner's syndrome result in one blue eye?
Need sympathetic stimulation for the development of iris pigment
191
Pharmacology of cocaine
- indirect-acting sympathetic agonist
| - binds to receptors on sympathetic nerve endings and prevents re-uptake of NE
192
How is cocaine used to diagnose Horner's syndrome?
- in a normally functioning system, effect is enhanced sympathetic activity
- with complete sympathetic disruption, cocaine will not have the expected effect (patient has Horner's)
193
Effects of cocaine (systemic and local)
- local anesthetic
- mydriasis
- increased heart rate
- vasoconstriction
- CNS stimulation
194
Clinical uses of cocaine
- diagnosis of Horner's syndrome
| - debridement of corneal epithelium
195
Side effects of cocaine
- CNS stimulation
- Death from respiratory failure
- rapid absorption from mucous membranes
- corneal damage with topical use
196
Contraindications of cocaine
- cardiac disease
| - hyperthyroidism
197
Hydroxyamphetamine drug type
Indirect mydriatic
198
Pharmacology of hydroxyamphetamine
- similar structure to NE
- indirect-acting adrenergic agonist
- causes release of endogenous NE
- if post-ganglionic neuron damaged (post-ganglionic Horner's), then no NE is released; no dilating effect
- little/no effect on accommodation
199
Clinical uses of hydroxyamphetamine
- mydriasis
- max at 45-60 minutes and lasts about 6 hours
- differentiation of pre- and post-ganglionic Horner's syndrome
200
What happens in central/pre-ganglionic Horner's after administration of hydroxyamphetamine?
Post-ganglionic fibers should have normal amounts of NE: DILATION would result
201
What happens in post-ganglionic Horner's after administration of hydroxyamphetamine?
No/little NE in post-ganglionic fibers: NO DILATION with hydroxyamphetamine
202
Side effects of hydroxyamphetamine
- little ocular irritation
- can cause elevated blood pressure
- may be safer to use for mydriasis in patients with phenylephrine CI
203
Apraclonidine (Iopidine) drug type
Direct-acting alpha-agonist (strong alpha-2, weak alpha-1)
204
Apraclonidine pharmacology
- causes decrease in IOP
| - little effect on pupil size in normal eye
205
What happens if you instill apraclonidine in a normal eye?
No/minimal dilation
206
What happens if you instill apraclonidine in a Horner's eye?
The pupil dilates (reversal of anisocoria)
207
Clinical uses of apraclonidine (Iopidine)
- prevents IOP spike following anterior laser procedures
| - DIAGNOSIS of Horner's (in lieu of cocaine test)
208
Primary use of Brimonidine
- management of glaucoma (not effective for Horner's due to more alpha-2 selectivity and negligible alpha-1 activity)
209
What are mydriolytics?
Alpha-adrenergic blocking agents used to reverse mydriasis (safer than miotics)
210
Dapiprazole pharmacology
- mydriolytic
- alpha-adrenergic antagonist
- produces miosis
- reduces IOP
- no shallowing of the AC
- may be useful in angle closure
- may partially increase AA caused by tropicamide
- slower effect in dark irises
- minimal systemic absorption
211
Clinical uses of dapiprazole
- reversal of pupillary dilation (phenylephrine)
- partial reversal of pupillary dilation (tropicamide)
- LITTLE EFFECT ON CYCLOPLEGIA
- angle closure glaucoma??
212
Dapiprazole side effects
- burning
- conjunctival hyperemia, chemosis
- punctate keratitis; edema
- ptosis
- brow ache
- no effect on blood pressure or pulse rate
213
Contraindications of dapiprazole
- anterior uveitis
| - hypersensitivity
214
What bacteria are we most concerned about in contact lens wearers?
Pseudomonas
215
What are the most common bacteria that cause ocular infections?
Staphylococci and Streptococci (Gram +)
216
What are other bacteria that cause ocular infections that are not Gram (+) cocci?
- Gram (-): Neisseria gonorrhea, Haemophilus influenzae, E. coli, Serratia marcescens, Proteus, Pseudomonas aeruginosa
- chlamydia
- treponema pallidum (spirochete)
217
If you can't determine cause of a red eye, what should you do?
Have patient RTC in 1-2 days to re-evaluate. The red eye will eventually declare itself
218
Adverse consequences of antibiotic use
- allergic reactions
- superinfection - another organism is allowed to overgrow (yeast)
- resistance
219
What are methods for minimizing potential for resistance?
- use narrowest spectrum agent possible for given infection
- use proper dose
- use shortest effective duration of therapy, but finish course
- DO NOT TAPER
220
Drugs that affect cell wall synthesis
- penicillins
- cephalosporins
- vancomycin
- bacitracin
221
Which of the drugs that affect cell wall are available in an ophthalmic ointment?
Bacitracin
222
Commonalities between beta-lactams
- all can cause hypersensitivity reactions
- all share a common basic MOA (bind to PBPs)
- all lack activity against atypical organisms (mycoplasma, chlamydia, ricketts, etc.)
- all LACK activity against MRSA
223
What are penicillins?
- beta-lactam ring connected to a side chain
- beta-lactam ring must be intact for activity
- divided into four categories
224
MOA of penicillins
- inhibits synthesis of cell wall by inhibiting cross-linking of polysaccharide chains of peptidoglycan
- works on actively dividing cells (once it's formed, there's no effect)
- osmotic pressure causes lysis of the cell
225
What are the four basic categories of penicillins?
- natural penicillins
- antistaphylococcal penicillins
- aminopenicillins
- anti-pseudomonal penicillins
226
What are the natural penicillins and what is their spectrum of activity?
- penicillin G - IM only
- penicillin V - oral
- Staph became resistant quickly so now has a very narrow spectrum
- good: treponema pallidum (DOC), most strep
- moderate: strep pneumoniae
- poor: almost everything else (staph)
227
What are antistaphylococcal penicillins?
- methicillin - defines class
- oxacillin
- cloxacillin
- dicloxacillin
- nafcillin
228
What is the spectrum of activity of antistaphylococcal penicillins?
- good: MSSA, streptococci
- poor: Gram (-) rods, MRSA
- TOC: Vancomycin (in flux because now we have VRSA!)
229
What is an ocular indication for oral antistaphylococcal penicillins?
- internal hordeolum (MSSA): oral cloxacillin or dicloxacillin
- preseptal cellulitis (MSSA): dicloxacillin 250mg qid
- orbital cellulitis: IV nafcillin
230
What patient history would make you suspect MRSA?
- patient works in a hospital/nursing home
- patient lives in a correctional facility or college dorm
- MRSA can also be out in the community
231
What are some aminopenicillins and what is their route of administration?
- amoxicillin (oral)
| - ampicillin (IV)
232
What is the spectrum of activity of aminopenicillins and what diseases are they used to treat?
- good: streptococci, enterococci
- moderate: H. influenzae, E. coli
- poor: staph
- URI (strep throat), otitis media
233
What are beta-lactamase inhibitors used for?
- can counteract beta-lactamases and extend spectrum of aminopenicillins and antipseudomonal penicillins
- beta-lactamase inhibitors have little antimicrobial activity by themselves
234
What are some examples of beta-lactamase inhibitors?
- clavulanate
- sulbactam
- tazobactam (only added to antipseudomonal pcn)
235
What is Augmentin a combination of?
- amoxicillin
| - clavulanic acid
236
What is Unasyn a combination of and what is its route of administration?
- ampicillin
- sulbactam
- administered IV
237
Sensitivity of beta-lactamase inhibitors
- good: MSSA, strep, E. coli
| - poor: MRSA
238
Ocular indications for Augmentin
- preseptal cellulitis
- dacryocystitis
- pediatric haemophilus
239
Is Augmentin safe in pregnancy?
Yes
240
Typical adult dose of Augmentin
- 500 mg BID or 250 mg TID
| - more severe: 875mg BID or 500mg TID
241
What are some examples of antipseudomonal penicillins?
- piperacillin
- carbenicillin
- mezlocillin
- ticarcillin
242
What is the spectrum of activity of antipseudomonal penicillins?
- good: P. aeruginosa, strep, enterococci
- moderate: haemophilus
- poor: staph, anaerobes
243
What are the side effects of penicillins?
- hypersensitivity
- alteration of normal flora (super-infection)
- failure of oral contraceptives (although not clear which oral antibiotics cause this)
244
Contraindications to penicillins
- known hypersensitivity to any penicillin
| - cross-sensitivity with cephalosporins
245
Are there any topical ophthalmic preparations of cephalosporins?
No
246
What is the preferred oral 1st generation cephalosporin?
Cephalexin (Keflex)
247
What is the preferred oral 2nd generation cephalosporin?
Cefaclor (Ceclor)
248
What is the preferred oral 3rd generation cephalosporin?
Cefixime (Suprax)
249
What are common 1st generation cephalosporins we need to know for this exam?
- Cefazolin (important in cornea, must be compounded)
| - Cephalexin (500 mg BID)
250
What is the spectrum of activity of first generation cephalosporins?
- Good: MSSA, streptococci
| - Poor: MRSA, pseudomonas
251
Ocular indication of Cefazolin?
DOC for bacterial corneal ulcers when using a traditional "broad-spectrum" approach
252
Ocular indications of cephalexin?
dacryocystitis, preseptal cellulitis if MSSA
253
What are common 2nd generation cephalosporins we need to know for this exam?
- cefaclor (Ceclor)
| - cefuroxime (Ceftin)
254
What is the spectrum of activity of 2nd generation cephalosporins?
- more effective against gram (-) than first generation
- particularly good against Haemophilus & Neisseria
- "HENPEK"
- good: Haemophilus, Enterobacter, Neisseria, Proteus, E. coli, Klebsiella
- moderate: strep, staph
- poor: MRSA, pseudomonas
255
Ocular indications of oral cefaclor?
dacryocystitis, preseptal cellulitis (MSSA, haemophilus)
256
Ocular indications of parenteral cefuroxime?
severe dacryocystitis, preseptal cellulitis in a child
257
What are some 3rd generation cephalosporins we need to know for this exam?
- ceftazidime
- ceftriaxone
- cefixime (Suprax - oral)
258
What is the spectrum of activity of third generation cephalosporins?
- increasing gram (-) coverage
- decreasing gram (+) coverage
- good: strep, pseudomonas (ceftazidime)
- moderate: MSSA
- poor: MRSA, pseudomonas (except ceftazidime)
259
Ocular indications of third generation cephalosporins?
IV ceftriaxone for orbital cellulitis (in combo)
260
Side effects of cephalosporins?
- rash
- fever
- bronchospasm
- rare anaphylaxis
- uncommon cross hypersensitivity with penicillins
- alteration of normal flora
- vitamin K deficiency
- reversible renal impairment
261
Contraindications to cephalosporins
- known hypersensitivity
- hemophilia (due to vitamin K issues)
- anaphylaxis to penicillin, but would be ok to Rx if had delayed hypersensitivity to PCN
262
MOA of bacitracin?
inhibits the polysaccharide chain formation in cell wall synthesis
263
Spectrum of activity of bacitracin?
Gram (+), plus Neisseria
264
What is the formulation of bacitracin?
only available in an ointment because it's not soluble
265
What ocular conditions is bacitracin used to treat?
staph blepharitis - in combo with Polymyxin B (Polysporin) or Polymyxin B/Neomycin (Neosporin)
266
Side effects of bacitracin?
- hypersensitivity (dermatitis) is rare
| - considered non-toxic and is well-tolerated when used topically
267
MOA of vancomycin
- inhibits synthesis of cell wall precursors
| - inhibits RNA synthesis
268
What is the spectrum of activity of vancomycin?
- Gram (+) cocci (MRSA), Neisseria, Clostridium, Corynebacterium
269
Is there an ophthalmic preparation of vancomycin?
No
270
What are some systemic indications to use vancomycin?
- TOC for C. diff infections
- TOC for MRSA and penicillin-resistant S. pneumoniae (IN FLUX)
- only used when REALLY necessary
271
What are some ocular indications for vancomycin?
- bacterial endophthalmitis (intravitreal)
| - resistant blepharitis, keratitis
272
Side effects of vancomycin
- permanent deafness
- fatal uremia
- red man syndrome
273
MOA of polymyxin B
- detergents interact with the phospholipids of the cell's membranes
- doesn't need actively dividing cells to work
274
Spectrum of activity of polymyxin B
Mostly Gram (-)
275
Clinical uses of Polymyxin B
used topically in combination for conjunctival and lid infections (minor things)
276
Combinations of polymyxin B (3)
- polymyxin B and bacitracin (Polysporin) has good Gram (-) and (+) coverage
- polymyxin B and trimethoprim (Polytrim) is broad-spectrum and well-tolerated; inexpensive; good for bacterial blepharitis or prophylaxis from corneal erosion
- polymyxin B and bacitracin and neomycin (Neosporin) is not prescribed often due to hypersensitivities to neomycin
277
Side effects of systemic polymyxin B
neurotoxicity and nephrotoxicity
278
Side effects of topical Polymyxin B
mild and infrequent
279
Classes of drugs that affect protein synthesis (6)
- aminoglycosides
- tetracyclines
- macrolides
- linezolid
- chloramphenicol
- clindamycin
280
Aminoglycoside drugs
- neomycin
- gentamicin
- tobramycin
- amikacin
281
Spectrum of aminoglycosides
- good: Gram (-) including some pseudomonas
- moderate: IN COMBO with beta-lactam: staph (including MRSA)
- poor: Gram (+) if used alone
282
How do bacteria become resistant to aminoglycosides?
- alteration of bacterial ribosomes (binding site)
- decreased antibiotic uptake
- enzymatic inactivation of the drug (most common)
283
What are the routes of administration of aminoglycosides?
IM, IV or topical due to poor absorption from the gut
284
Neomycin's spectrum of activity?
broad spectrum (different from other aminoglycosides)
285
Ocular indications of neomycin
topical surface disease (in combo or alone)
286
Ocular uses of gentamicin
- conjunctivitis
- blepharitis
- keratitis
- endophthalmitis
287
What is something to be aware of when prescribing gentamicin?
Can cause corneal toxicity - sloughing of epithelium with frequent dosing and prolonged use
288
Between gentamicin and tobramycin, which has better activity against pseudomonas?
Tobramycin
289
Ocular uses of tobramycin
- bacterial keratitis - fortified gentamicin or tobramycin with fortified cefazolin
- endophthalmitis - fortified gent/tobr with piperacillin/ticarcillin
290
Which of the aminoglycosides is preferred for endophthalmitis?
Amikacin (with vancomycin)
291
Systemic side effects of aminoglycosides?
- auditory and vestibular toxicity
| - nephrotoxicity
292
Systemic side effects of gentamicin?
- pseudotumor cerebri
- auditory and vestibular toxicity
- nephrotoxicity
293
Side effects of topical gentamicin
corneal/conjunctival toxicity
294
Side effects of intravitreal aminoglycosides (except amikacin)
macular infarction
295
Spectrum of activity of tetracyclines
- good: atypicals, rickettsia, spirochetes
- moderate: staph (including MRSA), strep
- poor: most gram (-) rods
296
When are tetracyclines the DOC?
- "oddball" infections: RMSF, lyme disease, chlamydia
297
Ocular indications of tetracyclines?
- infections (Adult inclusion conjunctivitis, AIC): doxycycline 100mg BID X 1-3 weeks
- soft tissue infection (ild)
- non-infectious conditions (acne rosacea, meibomianitis): therapy is long term, sub-antimicrobial dosing
298
Side effects of tetracyclines
- photosensitivity
- GI disturbance
- depressed bone growth in fetus/tooth discoloration
- pseudotumor cerebri (rare)
- vestibulotoxicity with minocycline
299
contraindications to tetracycylines
- hypersensitivity
- pregnant or lactating women
- children under 8 years old (8-13 controversial)
300
Prescribing warning with tetracyclines
- decreased absorption with dairy products, antacids containing calcium, magnesium, aluminum and sodium bicarbonate (baking soda)
- decreased absorption with food (tetracycline)
- esophagitis (doxycycline), so important to be upright for at least 30 minutes after taking and drink a glass of water
301
Short-acting tetracyclines and sig for treating trachoma?
- tetracycline
| - trachoma: 250 qid X 14 days
302
Examples of long-acting tetracyclines and their sigs
- doxycycline
- minocycline
- AIC: 100mg BID x 7 days
303
Spectrum of activity of macrolides
- mostly gram (+)
| - some gram (-)
304
What type of infections can macrolides be used to treat? And what can they substitute for?
- chlamydial infections, neisseria, treponema (good substitute for tetracyclines)
305
How do bacteria become resistant to macrolides?
alteration of the ribosome structure - Gram (+)
306
What are some drugs that are macrolides? And their available ROAs?
- erythromycin: topical ophthalmic and oral
- clarithromycin: oral only
- azithromycin: topical ophthalmic and oral
307
How is erythromycin administered?
- parenterally, orally and topically
| - gastric acid inactivates erythromycin base, so lots of formulations to stabilize and promote absorption
308
Ocular uses of erythromycin
- can be used orally for chlamydia in infants, children, pregnant women (250mg qid X 21 days for adult)
- can be used topically in staph lid disease
309
When is clarithromycin contraindicated?
pregnancy
310
What is the signatura for azithromycin when treating chlamydia?
take 2 tablets by mouth at the same time (1 g dose)
311
How is azithromycin ophth sol administered topically?
- days 1 and 2: 1 drop twice daily
| - days 3-7: 1 drop once daily
312
How can ODs use azithromycin off-label?
long-term therapy to treat meibomianitis and is applied to the lids
313
Side effects of macrolides
- GI disturbance
- cholestatic hepatitis (erythromycin estolate in adults)
- palpitations, HA, dizziness (azithromycin)
314
Spectrum of linezolid
- good: MSSA, MRSA, strep
- moderate: some atypicals
- poor: gram (-), anaerobes
315
Why isn't linezolid used very often?
it's reserved for severe hospital-acquired MRSA, so it's advised to only be used if you have to use it
316
Is there an ophthalmic preparation of linezolid?
No
317
Side effects of linezolid
- can cause bone marrow suppression, mostly after 2+ weeks
| - serotonin syndrome
318
adverse effects of linezolid
- potentially fatal
- confusion/agitation/tremor
- nausea/vomiting/diarrhea
- dilated pupils
- increased temperature/shivering/sweating
- very high fever/seizure/unconsciousness
319
spectrum of activity of clindamycin
- good: many gram (+) anaerobes
- moderate: s. aureus (including some MRSA), strep, chlamydia, toxoplasma gondii
- poor: c. diff
320
Is there an ophthalmic preparation for clindamycin?
No
321
Ocular indication for clindamycin
toxoplasmosis (may be effective against encysted form)
322
side effects of clindamycin
- pseudomembranous colitis (chloisteroides, c. dif), which can be very dangerous in older patients
- hypersensitivity (dermatitis)
- but generally well-tolerated
323
Drug classes that affect intermediary metabolism
- sulfonamides
- pyrimethamine
- trimethoprim
324
spectrum of sulfonamides
- broad spectrum
- gram (+), gram (-), chlamydia, plasmodia, toxoplasma
- but there is tons of staph resistance
325
how bacteria become resistant to sulfonamides
- overproduction of PABA
- decreased enzyme affinity for drug
- decreased cell permeability to drug
- inactivation of drug
326
what chemicals can negate the effects of sulfonamides?
- anesthetics contain PABA and can reverse the sulfonamide-induced inhibition of folic acid synthesis
- pus, blood in environment can decrease the bacterial requirement for folic acid
327
clinical uses of oral sulfonamides
- active toxoplasmosis infection in combination with pyrimethamine
- pneumocystis infections
328
clinical uses of topical sulfonamides
- primarily in combination with steroid for blepharitis
| - ALMOST never used topically in ophthalmic care today
329
side effects of sulfonamides
- mild: GI, skin reactions, transient myopia
- severe: SJS, blood dyscrasias
- topical: hyperemia, contact dermatitis, local photosensitivity
330
what drugs have synergistic activity with sulfonamides?
pyrimethamine and trimethoprim (work further down in the pathway)
331
clinical uses of oral pyrimethamine
toxoplasmosis (with sulfadiazine)
332
clinical uses of trimethoprim and sulfamethoxazole
UTI, MRSA cellulitis
333
clinical uses of trimethoprim and polymyxin B
ophthalmic drops good for bacterial blepharitis
334
spectrum of TMP/SMX (Bactrim, Septra)
- good: staph (some MRSA), haemophilus, pneumocystis jirovecii
- moderate: s. pneumoniae
- poor: pseudomonas, s. pyogenes
335
clinical uses of TMP/SMX
- uncomplicated UTI, pneumocystis pneumonia
- good choice for MRSA
- has a "double strength" available
336
side effects of pyrimethamine
- wbc and platelet suppression
| - folate deficiency
337
trimethoprim/sulfamethoxazole systemic side effects (3)
- skin reaction
- significant interaction with warfarin
- hematologic problems IF patient is folate deficient
338
is Bactrim a sulfonamide?
Yes
339
side effects of polytrim
- transient burning, stinging
- hypersensitivity - lid edema, rash
- NO CROSS-SENSITIVITY between sulfa and trimethoprim
340
contraindications of pyrimethamine and trimethoprim
- folate deficiency
| - pus is NOT a contraindication to Polytrim use
341
Drugs that affect DNA synthesis
- metronidazole
- rifamycins (Rifampin)
- quinolones (more pertinent to ODs)
342
spectrum of quinolones
good broad spectrum coverage
343
bacteria that have developed resistance to quinolones
- some pseudomonas resistance (2nd generation)
| - some staph resistance (2nd generation)
344
topical ophthalmic fluoroquinolone drug names
- ciprofloxacin (Ciloxan) - ointment and drops (1st gen)
- ofloxacin (Ocuflox) (1st gen)
- levofloxacin (2nd gen)
- moxifloxacin (Vigamox, Moxeza) (3rd gen)
- gatifloxacin (Zymaxid 0.5%) (3rd gen)
- besifloxacin (Besivance); 3rd gen; no generic available; never used as oral/systemic nor in livestock and feed
345
Why are fluoroquinolones not really used by ODs?
Huge black box warnings that keep getting longer
346
Oral fluoroquinolones that we need to know
- levofloxacin
- ciprofloxacin
- moxifloxacin
- ofloxacin
- gemifloxacin
347
Fluoroquinolone black box warnings
- increased risk of tendinitis/tendon rupture
- risk or worsening symptoms of MG
- potential irreversible peripheral neuropathy, CNS effects
348
Benefits of fluoroquinolones in eye care
- greater efficacy and broader spectrum of activity than bacitracin, erythromycin, gentamicin and tobramycin
- typically less toxic than aminoglycosides
349
Clinical uses of FQs (in OD practice)
- most are FDA approved for conjunctivitis
- ciprofloxacin and ofloxacin are FDA approved to treat keratitis
- moxi, gati, besi are used more often for keratitis off-label (newer)
350
Side effects of topical FQs
- local burning
- bitter taste
- white precipitate at base of keratitis (cipro)
- conjunctival hyperemia
351
FQ Contraindications with oral use
- known hypersensitivity
- erosion of cartilage in weight-bearing joints in immature animals
- tendon rupture
- inhibits metabolism of theophylline
352
Are FQs indicated if you suspect MRSA in a bacterial keratitis?
Not unless it's combined with trimethoprim
353
What is the Sanford Guide to Antimicrobial Therapy for bacterial keratitis with no comorbidities?
- Moxif 1 gtt/h X first 48 h then decrease
| - alternative: cipro, levo or gati drops
354
What is the Sanford Guide to Antimicrobial Therapy for bacterial keratitis for contact lens wearers?
- cipro or levo q1-2h X 24-72h
| - alternative: gent or tobra 0.3% hourly X 24h
355
What is the Sanford Guide to Antimicrobial Therapy for bacterial keratitis for dry cornea, diabetes, immunosuppression?
- cipro hourly
| - alternative: vanc + ceftazidime (each 50mg/mL) topical
356
What is the only topical ophthalmic anti-fungal preparation available in the US?
- natamycin (Nystatin)
357
What is the Sanford Guide for fungal keratitis?
- Natamycin 5% drops 1 gtt q1-2h for several days, then reduce
- alternative: amphotericin B 0.15% drops 1 gtt q1-2h for several days
358
Why are there fewer effective antiviral medications?
they have to interfere with viral replication without harming the host, which is difficult because the viruses use our own cellular apparatus
359
What are the five herpesviruses that cause ocular infection?
- herpes simplex 1
- herpes simplex 2
- varicella zoster (VZV)
- cytomegalovirus (CMV); usually problematic in AIDS patients
- Epstein-Barr virus (EBV) aka mono
360
Are there any approved antivirals for adenoviruses (most common infection in the eye)?
No
361
What symptoms occur in the primary infection of HSV?
- subclinical, flu-like symptoms
- small vesicles around eyes
- may have follicular conjunctivitis and/or corneal involvement
362
What symptoms occur in the recurrent disease of HSV?
- corneal involvement (1%)
| - oral involvement is the most common
363
What are triggers for recurrence of HSV?
- stress
- sunlight
- age
- illness (fever)
- injuries, etc
364
What are the three types of HSV keratitis?
- epithelial keratitis (dendrites)
- stromal keratitis (edema, anterior chamber rxn)
- endothelial keratitis
365
What is the leading cause of corneal blindness in the US?
stromal HSV keratitis
366
Current topical anti-herpes medications
- Trifluridine (Viroptic)
| - Ganciclovir (Zirgan)
367
MOA of trifluridine
inhibits thymidine synthetase and DNA synthesis in virus-infected and normal cells
368
What preservative does use trifluridine use?
thimerosal and some patients don't do well with it
369
Clinical use of viroptic and instructions for use
- treatment of HSV epithelial keratitis
- 1% gtt q2h (max 9x/d) until re-epithelialized, then q6h for 3-7 days
- treat no longer than 21 days
- superior to IDU and Vidarabine for treatment of geographic and dendritic ulcers
370
Side effects of viroptic
- burning/irritation
- punctate keratopathy
- corneal edema
- dry eye
- conjunctival hyperemia
371
MOA of ganciclovir
- competitively inhibits DNA polymerase
| - incorporates into DNA primer strand (terminates strand)
372
clinical indications of ganciclovir ophthalmic gel (Zirgan)
- acute epithelial HSK (as effective as topical acyclovir)
373
Sig of ganciclovir
- 1 gtt 5X/day until re-epithelialization, then 3X/day for additional 7 days
374
Ganciclovir adverse events
- blurred vision (gel)
- ocular irritation
- punctate keratitis
- conjunctival hyperemia
375
Possible alternative use of Zirgan (ganciclovir)
adenovirus conjunctivitis (off-label)
376
Treatment options for HSK
- trifluridine (Viroptic) - refrigeration required prior to opening; 9x/d dosing; potential for more toxicity (works on all cells); thimerosol preservative; available generic ($70)
- ganciclovir (Zirgan) - minimal toxicity (works only in infected cells); 5x/d dosing; no refrigeration; BAK preserved; no generic available ($400)
377
what is acyclovir?
synthetic purine analog to guanine
378
Is there a topical acyclovir in the US?
no
379
MOA of acyclovir
- phosphorylated by herpes-specific thymidine kinase
- acyclovir triphosphate inhibits herpes-specific DNA polymerase (selectively toxic)
- very little resistance in immuno-competent patients
380
Available ROA of acyclovir
oral and IV
381
clinical uses of TOPICAL acyclovir
- treatment of HSK in Europe and Canada
382
Side effects of TOPICAL acyclovir
- punctate keratitis
| - burning/stinging
383
clinical uses of ORAL acyclovir
- has been shown to be as effective as topical acyclovir in EPITHELIAL HSK (which is as effective as IDU, vidarabine, or trifluridine)
384
sig of oral acyclovir
400mg PO 5x/d
385
does use of long-term oral acyclovir prophylactically reduce recurrence in immunocompetent patients?
Yes, but patients may want periodic renal function tests
386
What is the sig for using oral acyclovir to treat herpes zoster?
800mg orally 5x/d for 7-14d
387
Is oral therapy required to treat VZV?
Yes
388
How soon after symptoms of VZV does treatment have to begin to prevent severe complications? And what are the severe complications?
- 72 hours
- decreases ocular inflammation
- reduces post-herpetic neuralgia
389
Side effects of oral acyclovir
- nausea, vomiting, diarrhea
- headache
- rash
390
contraindications to acyclovir
- known hypersensitivity
- renal insufficiency - MONITOR
- lactose intolerance (generics)
391
what is the sig for acyclovir when suppressing HSV in select patients?
400mg BID, indefinitely
392
sig for valacyclovir (Valtrex) to treat epithelial HSK and zoster
```
epithelial HSK:
- active: 500mg BID-TID
- prophylaxis: 500mg QD
and zoster:
- 1g TID x 7-10 days, maybe 14 days in some cases
```
393
sig for famciclovir (Famvir) to treat epithelial HSK and zoster
HSK:
- 250 mg TID X 7-10 days
zoster:
- 500mg TID X 7-10 days
394
Which drug is the DOC for HSK & VZV in elderly patients?
Famciclovir because acyclovir and valacyclovir have an increased risk of CNS adverse reactions in these patients?
395
What is the DOC for HSK & ZVZ in neonates?
acyclovir
396
What is the DOC for treating HSK & VZV in 2-18 year olds?
acyclovir or valacyclovir
397
What drugs are used for initial presentation of HSV conjunctivitis and their sig?
- Trifluridine (Viroptic) gtts q2h (up to 9x/d), or
| - ganciclovir 5x/d
398
Are steroids contraindicated in corneal epithelial disease?
YES (WILL BE ON TEST)
399
When would oral antivirals be preferred over topicals?
- patient physically unable to use drops
- contact lens wearers?
- pediatric patients' refractory to topical antiviral (not responding)
- patients that require length treatment antiviral agents
- patients with pre-existing ocular surface diseases, who may be more susceptible to toxicity
- prophylactic treatment after ocular surgery
400
When would topical antivirals be preferred?
- patients with renal impairment
- elderly patients (>64 yrs) with renal impairment or when renal function is unknown at the time of drug administration
- pregnant patients
- nursing mothers
401
What is the standard therapy of STROMAL HSK?
- aim is to decrease inflammation/scarring
- if very mild, off-axis: topical cycloplegic/tears only
- not mild: topical trifluridine qid (or ganciclovir) AND
- topical steroid
- very slow taper needed, otherwise inflammation returns
- can d/c topical antiviral when steroid is once daily
402
How to treat stromal edema HSV with epithelial ulceration?
- Prednisolone 1% gtt twice daily PLUS
- acyclovir 800mg 3-5 times daily for 7-10 days OR
- valacyclovir 1g 3 times daily for 7-10 days OR
- famciclovir 500mg twice daily for 7-10 days
403
How to treat endothelial keratitis? (will see crazy inflammation, KP, cells & flare in AC with active virus)
- prednisolone 1% gtt 6-8 times daily PLUS
- acyclovir 400mg 3-5 times daily OR
- valacyclovir 500mg twice daily OR
- famciclovir 250mg twice daily
404
What are topical corticosteroid options for HSV?
- fluorometholone 0.1% ophthalmic suspension
- rimexolone 1% ophth susp
- prednisolone sodium phosphate 1% ophth sol
- prednisolone acetate 1% ophth susp
- difluprednate 0.05% ophth emulsion
405
potential indications for prophylaxis of recurrent HSV keratitis?
- multiple recurrences of any type of HSV keratitis (especially stromal)
- recurrent inflammation with scar/vascularization near visual axis
- more than one episode of HSV keratitis with ulceration
- post-keratoplasty performed for HSV-related scarring/astigmatism
- postop in patients with a history of HSV ocular disease undergoing any type of ocular surgery
- in patients with a history of ocular HSV during immunosuppressive treatment
406
what is the mainstay of therapy for HZV (shingles)?
oral antivirals
