Week 1- Therapeutics in Opthalmic Disease Flashcards
Name 3 barriers to ocular drug delivery
- Cornea
- Blood-Ocular Barrier
- Avascular tissues (Cornea+Lens)
What are the three topical preparations?
- Solutions
- Suspensions
- Ointments
What is the benefit of using an ointment over a suspension/ solution?
Ointments increase contact time, provide lubrication and protect against dessication
What are the two most common mydriatics?
- Tropicamide 1%
- Atropine 1%
What is the function of mydriatics?
Paralyse the smooth muscle sphincters and cilliary body
What are the four considerations for mydriatics?
- Reduced tear production in KCS
- Induces ocular hypertension and IOP
- Salivation in cats as is very bitter
- Mydriasis (lens luxation)
What is phenylephrine specifically used for?
- Localisation of horner syndrome
- 0.2-1% Phenylephrine
- Mydriasis in <20 minutes
Name three local anaesthetics for the eye
- Tetracaine
- Lidocaine
- Proxymetacaine
onset 5 minutes duration 2 hours
What are the considerations for local anaesthetics in the eye?
- Reduced corneal sensation
- Reduced sensation
- Epitheliotoxic
- Systemic toxicity when used in very small patients
What is the function of tear substitutes?
- Provide lubrication
- Improve Comfort levels
What is the function of tear stimulators?
Increases tear production
* however they need residual lacrimal tissue to work
What are ocular antivirals commonly used for?
Herpetic Keratoconjunctivitis in cats
Name two ocular antivirals
- Famcyclovir
- L-Lysine (oral supplement)
What is the benefit of corticosteroids in the eye?
- Inhibit chemotaxis
- Reduce exudation of protein and cells
- Stabilises the blood aqueous barrier
Nmae the two ocular corticosteroids
- Prednisolone acetate 1%
- Dexamethasone 0.1%
Name the three Ocular NSAIDS
- Keratolac
- Flurbiprofen
- Diclofenac
When should you avoid using Diclofenac and Flurbiprofen
Avoid in cases with Intra-Ocular haemorrhage because of inhibitory effect on platelet function
When would you use Anti-Allergy drugs?
Oral antihistamines, e.g chlorphenamine may be useful for dogs with allergic conjunctivitis
When would you use immunomodulatory agents?
- Cyclosporine and tacrolimus are calcineurin inhibitors they block lymphokine production
Name three topical NSAIDs
- Keratolac
- Flurbiprofen
- Diclofenac
Why should you avoid Diclofenac and Flurbiprofen in cats?
Diclofenac and Flurbiprofen increase IOP significantly in cats- avoid in cats
