Eye Flashcards
T/F topical drugs for eye can be used for systemic absorption like on the skin.
False; local absorption only
How should the dose of topical eye medications be increased?
increased concentration (not volume)
what are the two mediums eye medications come in?
ointment and drops
what are the disadvantages of drops?
- hard to hold eye open
- less duration of effect
- need to use more frequently
what are the advantages and disadvantages of ointments?
Advantages:
- better adherence to eye
- better exposure to drug
- less leakage down nasolacrimal duct
- less frequent application
Disadvantage:
- blurry vision for longer time
when should ointments for the eye be applied?
night
You have prescribed drops and an ointment. What order should they be applied in?
drops than ointment
What is the most common dosage form for eyes?
Liquid eye drops
How many drops should you prescribe?
1 is all that is needed, 2 are prescribed incase some rolls out of eye
more than 2 increases toxicity and cost without benefit
what is 1 drop equivalent to?
1 drop = 1 ggt = 1/20 cc = 0.05 cc
How do you put eye drops in?
- wash hands
- shake if suspension
- hold lower lid down to hold pouch between eyelid and ball
- brace hand against cheek or nose
- look at sky
- apply drops into pouch (or apply 1/2 in. of ointment here)
- don’t touch tip of applicator on anything
What is the mechanism of absorption of the eye?
local effect of drug on the eye is by diffusion into the eye
where does systemic absorption of eye medications occur? what do they cause?
nasolacrimal duct
S/E
how can you prevent systemic absorption?
nasolacrimal occlusion
- put drops in the eye, close the eye, apply gentle pressure on the inner cants for 1-2 minutes
- this decreases the exposure to the nasolacrimal apparatus & systemic absorption
what are ocular inserts?
- patient applies
- prolonged exposure
- often only need to apply weekly
- CL with drug implanted for LT drug use
What are the 6 major groups of drugs used in the eye?
- glaucoma medications
- lubricants
- vasoconstrictors (decongestants)
- antihistamines
- ocular corticosteroids
- ocular antibiotics
What is glaucoma?
elevated IOP due to increased aqueous humor and decreased drainage that kills optic nerve causing blindness
Compare and contrast open-angle glaucoma and closed/narrow-angle glaucoma.
open:
- slow
- chronic loss of vision
- topically tx fairly easily
closed:
- rapid loss of vision
- surgery required
How do glaucoma drugs work (2 ways)?
- decreased production of fluid
- change anatomy of eye so more fluid is drained
First line drugs for glaucoma?
- prostaglandin analogs
- beta blockers
- alpha agonists
second line drugs for glaucoma?
- carbonic anhydrase inhibitors
- cholinomimetics
MOA of prostaglandin analogs?
increase drainage of aqueous humor; most effective groups
S/E of prostaglandin analogs?
- hyperemia (redness)
- punctate erosions
- blurred vision
- change the color of iris permanently
- hypertrichosis (increased hair)
What are the different types of prostaglandin analogs available?
- latanoprost
- bimatoprost
- travoprost
what is the MOA of beta blockers?
decreased secretions of aqueous humor
S/E of beta blockers?
Local:
- stinging
- blepharitis
- blurred vision
Systemic:
- hypotension
- low HR
- heart failure
- worsening asthma
What are the beta blockers used in glaucoma?
- timolol
- carteolol
- levobunolol
what is the MOA of alpha agonists?
- decrease production
2. increases outflow of aqueous humor
What are the S/E of alpha agonists?
Local:
- allergic rxn
Systemic:
- dizziness
- fatigue
- sleepy
- dry mouth
- decreased BP
What are the alpha agonists used for glaucoma?
- apraclonidine
- brimonidine
What is the MOA of carbonic anhydrase inhibitors?
reduce the production of aqueous humor
S/E of carbonic anhydrase inhibitors?
Local:
- stinging
- tearing
- blurred vision
What are the two types of carbonic anhydrase inhibitors available?
Topical - dorzolamide - brinzolamide Oral - acetazolamide
MOA of cholinomimetics for glaucoma?
stimulate contraction of ciliary muscle which pulls open the trabecular meshwork and relieves IOP (increases drainage of humor)
S/E of cholinomimetics?
Local:
- miosis (decreased night vision)
- HA
- periorbital pain
Examples of cholinomimetics for glaucoma?
pilocarpine; has to be used several times a day (2nd line)
What is used to treat dry eyes?
lubricants
what are the 3 types of lubricants available?
- artificial tears
- lubricating ointments
- restasis
MOA of artificial tears?
- stimulate tears
- decrease evaporation of tears
S/E of artificial tears?
irritation if preservative present in preparation
Disadvantages of artificial tears?
- short duration of action
- need to be used a lot
Tx with artificial tears?
2x/day and increase
can use every hour if needed
OTC
available in single dose (preservative free)
or multi dose with preservative
MOA of lubricating ointments?
- stimulate tears
- decrease evaporation of tears
Advantages and disadvantages of ointments?
- more occlusive
- blurry vision
cyclosporine (restasis) MOA?
immunosuppressant used topically for chronic dry eye
it working suggests chronic inflammatory process in dry eyes
S/E of cyclosporine?
Local:
- stinging
- increased infections
Disadvantages to cyclosporine?
- takes a long time to work
- need to keep using to get effect
- expensive
- only Rx for dry eyes
Vasoconstrictor MOA?
alpha agonist that decreases redness by temporarily constricting blood vessels (eye decongestant)
S/E of vasoconstrictors?
Local:
- rebound
- increased IOP
- local irritation
Systemic:
- adrenergic agonist effects
Vasoconstrictors on the market for the eye?
- naphazoline
- tetrahydrozoline
- oxymetazoline
MOA of ocular antihistamines?
inhibit release of histamine from mast cells
examples of anthistamines?
- alcaftadine
- azelastine
- bepotastine
- olopatadine
- emedastine
- epinastine
- ketotifen
MOA of ocular antibiotics?
kill bacteria
uses for ocular antibiotics?
- conjunctivitis
- blepharitis
- keratitis
- styes
- prophylactically
- pre/post op
examples of ocular antibiotics?
- besifloxaxin
- moxifloxacin
- gatifloxacin
- erthromycin
- gentamycin
- suflacetamide
- tobramycin
MOA of ocular corticosteroids?
decreases inflammation in inflammatory eye conditions
S/E of ocular steroids?
Local: - increases IOP - infections - cataracts - scleral thinning - corneal melting Systemic: - the usual
Examples of ocular corticosteroids?
- prednisolone
- dexamethasone
- difluprednate
- fluoromethalone
- loteprednol
What drugs are given systemically that cause adverse affects to eye?
- hydroxychloroquine
- chloroquine
- sildenafil
- corticosteroids
How does hydroxychloroquine and chloroquine affect the eye?
immunomodulator that deposits pigment in back of eye, can cause blindness with LT use
used for malaria
How does sildenafil (viagra) affect the eye?
a phosphodiesterase inhibitor may rarely cause blindness, more commonly can see color changes with its use
how do corticosteroids affect the eye?
increase IOP and cause cataracts
what drugs increase the risk of glaucoma?
- corticosteroids (eye or oral)
- anticholinergics (topical)
what drugs increase the risk of closed-angle glaucoma?
- anticholinergics (topical or oral)
- sympathomimetics (topical)
- anti-histamines
- anti-depressants
- topiramate
- phenothiazines
