Pharmacology: Optho Drugs Flashcards
Describe the mechanism of action of carbonic anhydrase inhibitors
Stop aqueous production
Name an ocular side effect of chloroquine
Maculopathy
Describe the mechanism of action of penicillins and cephalosporins
β-lactam ring inhibits the enzyme which makes bacterial cell wall → without cell wall bacteria die
Describe the mechanism of action for local anaesthetics
Blocks sodium channels and impedes nerve conduction
What is the indication for sympathomimetics?
Dilate the pupil before diagnostic/therapeutic procedures
⍺2 agonists used in refractory glaucoma)
Why should you not give chloramphenicol to newborns?
Newborns livers are unable to process chloramphenicol, results in grey baby syndrome
Describe the mechanism of action of quinolone antibiotics
Inhibit DNA gyrase, an enzyme that compresses bacterial DNA onto supercoils
Inhibition of DNA gyrase means nucleic acid synthesis is inhibited - supercoils unwind leading to cell death
What is ganciclovir?
Antiviral used in the management of dendritic ulcers of the cornea
Describe the mechanism of action of ⍺2 adrenergic agonists
Stop aqueous production and opens up drainage pathways for aqueous
Name an ocular side effect of rifampicin
Red tears (can stain contacts)
Name a contraindication for ⍺2 adrenergic agonists
Contraindicated in children
Name the most commonly used topical ocular antibiotic
Chloramphenicol
What is the indication for topical β-blockers e.g. timolol?
Second-line option for the management of glaucoma
Describe the indications for steroid eye drops
Used to suppress inflammation e.g. post cataract op, uveitis, prevent corneal graft rejection
What type of antibiotic is ofloxacin?
Quinolone
Name the route of administration of mydriatics
Topical
Name an ocular side effect of amiodarone
Corneal verticillata
Chloramphenicol is bactericidal for which organisms?
Strep. and Haemophilus
What is the indication for topical ⍺2 adrenergic agonists e.g. brimonidine?
Sympathomimetic drug which is an alternative option for the management of glaucoma
Describe the mechanism of action of chloramphenicol
Inhibits peptidyl transferase enzyme (inhibits bacterial protein synthesis)
When might antihistamines and mast cell stabilisers be used in ophthalmology?
Hayfever/allergic conjunctivitis
Name the route of administration for ganciclovir
Topical or systemic
Name two contraindications for steroids
Inappropriate use of steroids can result in the proliferation of herpes simplex keratitis
Do not use in dendritic ulcer - cause corneal melt
Describe the mechanism of action of prostanoids e.g. latanoprost
Open up drainage pathways for aqueous humour
Name the route of administration for ⍺2 adrenergic agonists
Topical
Chloramphenicol is bacteriostatic for which organism?
Staph.
What physical properties of chloramphenicol enable it to pass through the cornea?
It has both hydrophillic and hydrophobic properties
Describe the mechanism of action of ganciclovir
Inhibits viral DNA synthesis
Name an ocular side effect of alcohol and ethambutol
Optic atrophy
When might NSAIDs be used in ophthalmology?
Pain relief e.g. post refractive laser
Give two examples of steroid eye drops
Betamathasone, prednisolonce acetate
Name the route of administration for parasympathomimetics
Topical
Describe the mechanism of action for parasympathomimetics
Act on parasympathetic system to contract the pupillary sphincter, resulting in constriction of pupil (miosis)
Contraction of ciliary body changes shape of lens which allows more aqueous to drain
Why is compliance for parasympathomimetics poor?
4 x daily administration
Name the route of administration for latanoprost?
Topical
Name two ocular side effects of prolonged use of topical steroids
Cataract, glaucoma
Name two side effects of mydriatics
Blurring of vision
Can precipitate AACG
Describe the mechanism of action of topical β-blockers e.g. timolol
Reduce rate of production of aqueous humour
Name an ocular side effect of digoxin
Changes in colour appreciation
What is the indication for latanoprost (xalatan)?
First-line in the management of glaucoma
Describe the mechanism of action of sympathomimetics
Act on sympathetic system to cause pupil to dilate
Some cause cycloplegia (e.g. atropine), some do not (e.g. phenylephrine)
Describe the mechanism of action of steroid eye drops
Decreases transcription of inflammatory proteins and increases transcription of anti-inflammatory proteins
Name the route of administration of sympathomimetics
Topical
Penicillins and cephalosporins are classed as _______ antibiotics
β-lactam
Name the most commonly used diagnostic dye
Fluorescein
Describe the mechanism of action for mydriatics
Cause pupil dilation by blocking parasympathetic supply to iris
Stop lens from focusing (cycloplegia)
Name the route of administration for chloramphenicol
Ointment or drops
Name a side effect of parasympathomimetics
Night blindness
What is the indication for mydriatics e.g. tropicamide, cyclopentolate?
Applied before fundoscopy to aid examination
Name the route of administration for carbonic anhydrase inhibitors
Topical (dorzolamide)or systemic (acetazolamide)
What is the indication for carbonic anhydrase inhibitors?
Second-line option for the management of glaucoma
Name three indications for fluorescein
Shows corneal abrasion
Shows dendritic ulcer
Identify leaks
Name two contraindications for chloramphenicol
History of anaplastic anaemia, history of allergy
What is the indication for parasympathomimetics e.g. pilocarpine?
Alternative option for the management of glaucoma
Name an ocular side effect of vigabatrin
Field defect
Name two side effects of chloramphenicol
Allergy, irreversible anaplastic anaemia (rare)
Name the indication for prostinoids
First-line in the management of glaucoma
