L9 Flashcards
what is glaucoma eye drop
Most glaucoma drugs act by influencing the autonomic nervous system.
Aimed at reducing intraocular pressure (IOP)
what are the different categories of glaucoma eye drop
Cholinergics
Beta-adrenergic receptor blockers
Carbonic Anhydrase Inhibitors (CAI)
Prostaglandins
Adrenergic agonists
how deos miotic works and e.g of miotics
Effect exerted is through outflow
Contraction of the ciliary muscle pulls open the pores of the TM, thus increasing aqueous outflow.
E.g. Pilocarpine (Ocusert, Piloplex etc)
what is beta blocker and what is the effect of beta blocker
Originally developed for the treatment of cardiovascular disorders.
Beta receptors:
ß1: Mainly found in heart
ß2: Peripheral blood vessels, uterus, lungs
Function: Decreases aqueous production
what are the e.g of betablocker
Timolol (Timoptic, Betimol)
Levobunolol (Betagan)
Carteolol (Ocupress)
Betaxolol** (Betoptic)
** b1 selective, less risk to px with pulmonary disease
what is betaxolol
Better Visual Field preservation
Less systemic effects on circulation & respiratory system
what are the side effect of betablocker
Stinging sensation
Potentially reduce heart rate
Caution with patients with heart problems, lung problems, diabetes, depression due to drug interaction
what is carbonic anhydrase inhibitors and its e.g
Reduces aqueous secretion
Usually used in combination with other anti-glaucoma drugs
E.g.
Dorzolamide (Trusopt)
Acetazolamide (Diamox)
Oral
what is the side effect of CAI
Burning sensation
Bitter taste
Redness
Oral medication:
Depression
Weight loss
Kidney stones
Tingling sensation
what is prostalglandin and its e.g
increasing uveoscleral outflow
Originally discovered in the eye as chemical mediators of inflammation
However, it was later discovered that appropriate doses of PGs can lower IOP
E.g.
Latanoprost (Xalatan)
Travoprost (Travatan)
Bimatoprost (Lumigan)
why prostalglandin have better compliance
only require 1x/day instillation
what is uveoscleral outflow
Aqueous flows through the ciliary body into the suprachoroidal space (recall :space between the sclera & choroid).
There it is drained by the venous circulation of the ciliary body, choroid and sclera.
what are the side effect of prostalglandin
- Stinging & burning sensation
- Eye colour change due to increased iris pigmentation
- Lengthening of eyelashes
what is alpha -adrenergic agonist
a-Receptors consist of:
a1
a2
In the eye, a2 receptors are the predominant receptor in the iris & ciliary body.
Stimulation of a2 receptors can decrease aqueous humour production.
e.g of alpha adrenergic
Apraclonidine (Iopidine)
Brimonidine (Alphagan)
what are the side effects of alpha adrenergic agonist
Blood shot eyes
Lid elevation
Dilated pupils
Itching
what are hyperosmotic agent
Administered orally or intravenously
For people with severely high IOP
Useful in the mx of AACG
Osmotic gradient induced causes fluid to “move” from eye into blood vessels, thereby lowering the volume of fluid in the eye
Only a one time use
what are the e.g of hyperosmotic agent
Intravenous Agents
More effective
E.g. Mannitol
Oral Agents
E.g. Glycerin (Osmoglyn)
surgical technique for poag
trabeculoplaty - burn @ trabecular meshwork
trabeculectomy-a new drain is made in the eye so that fluid has a new escape route (through a scleral flap)
surgical method for aacg
iridotomy: making a tiny hole in the iris with a laser so that fluid can drain freely
iridectomy: surgical removal of part of the iris
future glaucoma therapy
need med that go beyond iop
- neuroprotection
- genetic therapy
-neuroregenration
