Flashcards in Pharmacology Deck (38):
What is needed for drugs to be able to work topically?
What kind of drugs are able to penetrate the epithelium?
Lipid soluble drugs
What kind of drugs are able to penetrate the stroma?
Water soluble drugs
What is added to topical steroids to make them more hydrophillic?
When is prednisolone acetate used?
Post operatively as has good penetration in uninflamed cornea and isn't washed away by tears
When is prednisolone phosphate used?
Cornea disease or when want low dose steroids
Use for surface of eye
What is added to topical steroids to make them more hydrophobic?
Acetate or alcohol
What is the role of Benzalkonium in topical drops?
Disrupts lipid layer of tear film
Aids penetration of some drugs
What is bimatoprost used to treat?
Lower IOP in glaucoma
What are steroids used topically to treat?
Post op cataracts
Prevent corneal graft
Local side effects of steroids on the eye
Exacerbation of viral infection
Systemic side effects of steroids
Neuropsychiatric side effects
What other snti-inflmmatory gents (other than steroids) are used in hayfever/allergic conjunctivitis?
Mast cell stabilisers
When would NSAIDs be used in ophthamology?
Pain relief (e.g. post refractive laser)
What is glaucoma?
A group of diseases characterised by progressive optic neuropathy resulting in characteristic field defects
What currently is the only modifiable risk factor for glaucoma?
Raised intra-ocular pressure
What classes of drugs are used to treatment glaucoma?
Carbonic anhydrase inhibitors
Alpha adrenergic agonist
Example of prostanoid
How do beta blockers work in glaucoma?
Work on cilliary bodies (turn off tap)
Example of topical & systemic carbonic anhydrase inhibitors
Topical - Dorzolamide
Systemic - Acetazolamide
How do carbonic anhydrase inhibitors help in glaucoma ?
Work on cilliary bodies (turn off ta)
How to alpha adrenergic agonists help in galucoma?
Example of parasympathomimetic drug
How do parasympathomimetics help in glaucoma?
Pulls iris tight to open up trabecular meshwork
Local side effects of parasympathomimetic
Difficulty seeing in the dark
What is first line management in glaucoma?
When is the intraitreal route of administration used?
Antibiotics in endophthalmitis
How does local anaesthetic work on the eye?
Blocks doium channels and impedes nerve conduction
When is local anaesthetic used in ophthalmology?
Tonometry (IOP measurement)
What is most common diagnostic dye used?
When is fluorescein used?
Show corneal abrasion
Diagnosing nasolacrimal duct obstruction
Examples of mydriatics
How do mydriatics work?
Cause pupil dilation by blocking parasympathetic supply to iris
Side effects of mydriatics
How do sympathomimetics work?
Act on sympathetic system
Cause pupil to dilate
Do not affect the ciliary muscle (accomodation)
Example of sympathomimetics
What are the ocular side effects of ethambutol?
Colour vision abnormalities