OAR Flashcards
What does Amiodarone treat? What are the OAR’s?
Cardiac arrhythmeia (class III agent- works by prolonging repolarisation in heart)
Corneal micro deposists (verticillata) - penetrate into lysosomes and bind with lipids inside cells which produces drug induce lipdoses (accumualtion of lipids) keratopathy
oral admin- lipophillic
400-1000mg (longer than 6months) 90%
Tears film /Aq humor or BV at the limbus
What are the 3 stages of Amiodarone Keratopathy
S1- fine grey/brown coalescent deposits linear fashion inferior cornea
S2- additional horizontal lines
- Aborizing
S3- Verticallate whorl like
Do fade usually between 3-20months after stopping
Found in basal cell layer of corneal epithelium
What are other OAR’s with Amiodarone?
Lens opacities Retinal $ ON deposits Optic neuropathy- disc swelling, indistinct boarders, bilateral vision loss, starts unilateral. 12month after start of medication glare halos blur SLIT LAMP!
What does Chlorpromazine treat?
Antipsychotic drug
What are the OAR’s for Chlorpromazine
Increase melanin production leading to pigment deposits on corneal Endo and DM
2000mg/day for 6months 12% corneal deposits
2500mg/day 90% lenticular deposits
some in posterior stroma, a sign that distributed via stroma
can cause stellate cats
What is Topirmate used for?
Antiepilectic
used for adults & children >2
What are the OAR’s for Topirmate?
Acute Onset Angle Closure Glaucoma -Ciliary body odema..pushes iris forward blocking the angle (secondary angle closure)...also swelling of CL Acute Myopia Peri-orbital oedema Scleritis Bleparospasm Nystagmus Diplopia
Who is more at risk for AACG in px taking Topirmate?
34 F
taking SSRI ^
first 2 weeks mean 7 days
What are the OAR’s for Tricyclic antidepressents (amitriptyline hydrochloride)?
Anti-muscarinic (ocular motor) pupil dilation and cyclo effect Photophobia - sun specs Blurred vision esp at near Risk of Angle closure
REVERSABLE EFFECTS
What are the OAR’s for motion sickness drugs (Hysoscine, scopolmine)
Anitmuscaranic effect (ocular motor) anti ach blocks vestibular signals
REVERSABLE
What are the OAR’s of sympathomimmetic drugs?
Angle closure
Pupil dilation
BV constriction (OTC could reduce conjunctival hyperemia) could miss potential eye disease
What is a Nystagmus?
A involuntary osscaltion of one or both eyes about one or more axes
What drugs can be asscoiated with nystagmus?
Verticle nystagmus and ptosis of eye lids- barbiturates (sedative)
Strepromycin (antibiotic)- Vestibular nystagmus dur yo CN8 interaction
How do thyroid drugs effect the eyes?
Synthetic hormones (levothyroxine, dextrothyroxine) neuromuscular blocking effects lead to diplopia and also ptosis
Papillodema, conjunctival hyperemia and odema, visual hallucinations,dry eye, photophobia
if excess thyroid, symptoms like myasthenia gravis
How does Heroin/methadone detoxifcation affect the eyes ?
Detox
Diplopia, blurred vision
deviaitions ^ ESO
reduced VA, redcuded stereoactuuty,reduce convg, reduced contrast sensitivity
How do antimuscarnic drugs affect the tears ?
Inhibit gland secretion reducing tear volume
KCS probs for CL wearer
How do antihistmamines, beta blockers, and oral contraceptives affec the tears film
decrease- KCS CL probs
How do paraysmpathomimetics affect the tears film (such as pilocarpine and neostigmine)?
increase tear production
What are general effects on the tears film?
inflamed glands or a reduction in nerve impluse so reflext tearing is reduced
How does blood pressure reduction relate to iop?
10mmHg in systolic BP reduction = 1-2mmHg IOP reduction
If a px is taking drugs to reduce blood pressure, what do we need to bare in mind?
BP lowering drugs:
may not need as much IOP lowering drugs
question medicine routine as effects are transient (1-4hrs) and pressure may rise after test
How do oral beta blockers effect IOP? (anenolol)
LOWER by decreasing aqueous production
How do vasodilators effect IOP (catopril)
LOWER by increasing aqueous outlflow
How do Achestarase inhibitors effect iop? (rivastigmine)
Lower by increasing aqueous outflow
How do systemic corticosteriods effect IOP?
Increase- increasse aq production and decreease outflow
are they a steriod responder?
topcial admin usually inc risk
Who is at risk of steriod induced CSCR? and what is the method at which it occurs ?
Middle aged men & stress
Inhibition of collagen synthase which ^ perm od choroid capilaries OR dyfunction of RPE - ^ fluid VA reduced and hyperopic shift
How often should IOP be measured in people taking corticosteriods ?
Before medcation starts
then at 1,3,6 months … then every 6month
What is an effect of corticosteriods?
PSC- 30% prevelence in those taking drug
dose dependant
10mg per day= low risk
16mg per day for several yrs = 75%
Drug reacts with amino groups in the fibres of the lens causing clumps
Why is PSC so trouoblesome ?
Cats close to nodal point of the eye
greater effect at near due to pupil constirction
Why is a PSC in children so harmful?
Could lead to amblyopia
Is a PSC reversabile ?
No unless its been short term (<2yrs) and a low dose
What drugs can unduce a myopic shift? How?
Suplhonamides
Diuretics
carbonic anyhdrase inhibitors
Topiramate
Odema of ciliary body -> zonualr relaxation
Odema of CL
Spasm of AA
What drugs are used for the management of Osteoporosis?
Bisphosphonates
Alendronate sodium, risedronate sodium
How do Bisphonates affect the eye?
anterior uveitis
conjucntivitis
episcleritis
scleritis
What is Chloroquine used to treat?
Anti-malarial drug and also treats rhemotoid arthiritis
What is a OAR of Chloroquine?
Narrowing of retinal BV
Bulls eye ring of pigment in the perimacular region
Pigmented tissue binds to drug -> degen of RPE->amsler scotoma
Vision normal until toxicity occurs later
dose dependant >300mg
What are the factors thaat ^ the risk of an OAR with the use of hdroxychloroquine?
Liver disease
60 or over
renal disease
Dose and retinal diseases
What are tetracylcines ?
group of bacteriostatic antibiotics
hyperpigmentiation aroound the eyes, palpebral conjunctiva
transient myopia, changes in colour vision, dipliopia
drug can get into to CSF-> papilodema
What is tamoxifen used for ?
Antiestrogen … used in treatment of breast cancer
What are the OAR’s for Tamoxifen?
bilateral maculopathy -fine yellow/white opacties -cystoid macula odema -parafoveal haem -rpe changes -va reduction 1yr >100mg
Check for colour defect (tritan)
What is vigabatrin used to treat ?
Epilepsy
What are the OAR’s for vigabtanib?
Bilateral VF loss-
What is Ethambutol used to treat?
TB
Optic neurpoathy- couple of months
VF defects- Central as pipillo macula bundle most effected
colour deciencies
