Pharmacology Flashcards
Explain the “sandwich” layers of the cornea?
- lipid
- water
- lipid
The epithelium of the cornea is ___hydrophobic/hydrophillic___
- hydrophobic
- lipophillic
The stroma of the cornea is ___hydrophobic/hydrophillic___
- hydrophilic
- lipophobic
Lipid solube drugs penetrate____
- the epithelium of the cornea
Water soluble drugs penetrate ____
- the stroma of the cornea
What can reduce the hydrophobic nature of the endothelium?
- ocular surface inflammation
An alcohol or acetate group added to a topical steroid has what affect?
- more hydrophobic
- can go through epithelium
A phosphate group added to a topical steroid has what affect?
- more hydrophillic
- through stroma
Prednisolone acetate is taken up where?
- actetate = hydrophobic, goes through epithelium
Prednisolone phosphate is taken up where?
- phosphate = hydrophilic, through stroma
What is a common preservative added to topical eye treatments?
- benzalkonium chloride
What drug is used 1st line to lower ICP in glaucoma?
- prostanoids
e. g. latanoprost
e. g. bimatoprost
What are steroids commonly used for in ophthalmology?
- post op cataracts
- uveitis
- to prevent corneal graft rejection
Temporal arteritis has what risk in the eyes?
- anterior ischaemic neuropathy
Side effects of steroids?
- cataracts
- glaucoma
- exacerbation of viral infections
What should NOT be given to a red eye patient?
- DO NOT give steroids to a red eye patient before examining with a split eye to ensure no dendritic ulcers
Define glaucoma?
- a group of diseases characterised by a progressive optic neuropathy resulting in characteristic field defects
Glaucoma on fundoscopy?
- central cup of optic nerve increases
What is the main aim of glaucoma treatment?
- bring intraocular pressure down
What are some 2nd line glaucoma treatments?
- beta blockers
- carbonic anhydrase inhibitors
How do local anaesthetics work on the eye?
- blocks sodium channels and impedes nerve conduction
What is the aim of mydriatics?
- dilate the pupil
Tropicamide is what class of drug?
- mydriatics
How do mydriatics work?
- block parasympathetic supply to iris
- block sphincter pupillae
- dilate pupil
What is the affect of sympathomimetics?
- dilate pupil
- stimulate sympathetic pathway
What is the aim of parasympathomimetics?
- constrict pupil
What is an ophthalmology side effect of ethambutol?
- optic neuropathy
What is an ophthalmology side effect of chloroquine?
- maculopathy
