Pharmacology Flashcards
What is needed for drugs to be able to work topically?
Corneal penetration
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?
Phosphate
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?
Preservative
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
Uveitis
Prevent corneal graft
Local side effects of steroids on the eye
Glaucoma
Cataract
Exacerbation of viral infection
Systemic side effects of steroids
Gastric ulceration Immunosuppression Osteoporosis Weight gain DIabetes Neuropsychiatric side effects
What other snti-inflmmatory gents (other than steroids) are used in hayfever/allergic conjunctivitis?
Antihistamines
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?
Prostanoids Beta blockers Carbonic anhydrase inhibitors Alpha adrenergic agonist Parasympathomimetic
Example of prostanoid
Latanoprost
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?
Increase outflow
Example of parasympathomimetic drug
Pilocarpine
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?
Prostanoid
When is the intraitreal route of administration used?
Antibiotics in endophthalmitis
Intra-ocular steroids
Anti-VEGF
How does local anaesthetic work on the eye?
Blocks doium channels and impedes nerve conduction
When is local anaesthetic used in ophthalmology?
FB removal
Tonometry (IOP measurement)
Corneal scraping
Comfort
What is most common diagnostic dye used?
Fluorescein
When is fluorescein used?
Show corneal abrasion
Tonometry
Diagnosing nasolacrimal duct obstruction
Angiography
Examples of mydriatics
Tropicamide
Cyclopentolate
How do mydriatics work?
Cause pupil dilation by blocking parasympathetic supply to iris
Side effects of mydriatics
Blurring
AACG
How do sympathomimetics work?
Act on sympathetic system
Cause pupil to dilate
Do not affect the ciliary muscle (accomodation)
Example of sympathomimetics
Phenylephrine
Atropine
What are the ocular side effects of ethambutol?
Colour vision abnormalities
Optic neuropathy
Side effects of chloroquine
Maculopathy
