pharmacology Flashcards
for which bacteria is chloramphenicol bactericidal
strep and haemophilus
what is the most commonly used topical antibiotic in ophthalmology
chloramphenicol
for which bacteria is chloramphenicol bacteriostatic
staph
why can we not give chloramphenicol to new borns
livers cant handle it resulting in grey baby syndrome
who do we avoid chloramphenicol in
history of aplastic anaemia
give an example of a quinolone
ofloxacin
MOA of quinolones
inhibit DNA gyrase
role of DNA gyrase
compresses bacterial DNA onto supercoils
management of dendritic ulcers of the cornea
ganciclovir
MOA of ganciclovir
inhibits viral DNA synthesis
give 2 examples of steroid eye drops
betamethasone, prednisolone acetate
name 3 patients who may receive steroid eye drops
- post cataract op
- uveitis
- prevent corneal graft rejection
MOA of steroid eye drops
decreases transcription of inflammatory proteins and increases transcription of anti-inflammatory proteins
what can be caused by inappropriate use of steroid eye drops
proliferation of herpes simplex keratitis
why can’t you use steroid eye drops in dendritic ulcers
causes corneal melt
name some complications of prolonged use of steroid eyedrops (4)
cataract
glaucoma
exacerbation of viral infections
raised intraocular pressure
give an example of a prostaglandin analogue
latanoprost
first line management of glaucoma
prostaglandin analogues
MOA of prostaglandin analogues
lower IOP by enhancing drainage of aqueous humour from the eye
what is second line in the management of glaucoma
β-blockers or carbonic anhydrase inhibitors
MOA of β-blockers in the eye
reduce the rate of production of aqueous humour
give an example of an anti-fungal used in the eye
natamycin
who gets prescribed antifungals for the eye (2)
fungal corneal ulcer
fungal retinitis / endophthalmitis
action of pilocarpine on the pupil
acts on M3 receptors found on the iris sphincter muscle causing the muscle to contract
pupil constriction
action of pilocarpine on the ciliary muscle of the eye
contracts the muscle promoting increased trabecular aqueous outflow
state the 2 main indications of pilocarpine
reduces IOP
prior to some laser procedures
name a topical and systemic carbonic anhydrase inhibitor
topical: dorzolamide
systemic: acetazolamide
MOA of carbonic anhydrase inhibitors
reduces the formation of aqueous humour
name a ⍺2 adrenergic agonist used in the eye
brimonidine
indication of ⍺2 adrenergic agonists in the eye
alternative management of glaucoma
who cant use ⍺2 adrenergic agonist
children
MOA of ⍺2 adrenergic agonist
stop aqueous production and opens up the drainage pathways
give an example of a Parasympathomimetics
pilocarpine
indication for pilocarpine
alternative management of glaucoma
name one side effect of pilocarpine
night blindness
why is there low compliance with pilocarpine
have to apply 4x a day so a bit of a pain really
MOA of local anaesthetic in the eye
blocks sodium channels and impedes nerve conduction
name some indications for local anaesthetic in the eye
foreign body removal
tonometry
corneal scraping
cataract surgery
what do we use to measure intraocular pressure
tonometry
most commonly used diagnostic dye
fluorescein
what is used to cause pupil dilatation before fundoscopy
mydriatics
name 2 adverse effects of mydriatics
blurring of vision
can precipitate AACG
what does AACG stand for
acute angle closure glaucoma
ocular side effect of vigabatrin
field defect
ocular side effect of alcohol (and ethambutol)
optic atrophy
ocular side effect of rifampicin
red tears
ocular side effect of digoxin
change in colour appreciation
ocular side effect of chloroquine
maculopathy
ocular side effect of amiodarone
corneal verticillata
what is an intracameral injection
injection into the anterior chamber of the eye
intravitreal injections
injection into the vitreous cavity
subtenon injection
injection between the sclera and tenon capsule
subconjunctival injection
injection under the conjunctiva
benefit of a subconjunctival injection
allows drug to bypass the corneal epithelium
name a common contaminant of bottles
psuedomonas
how long are bottles protected from contaminants
4 weeks
how can we limit the systemic absorption of topical drugs in the eye
holding the tear duct shut
