L9 Glaucoma Treatment Flashcards
how do antiglaucoma drugs help to reduce glaucoma?
Most glaucoma drugs act by influencing the autonomic nervous system.
- Aimed at reducing intraocular pressure (IOP)–help glaucoma px by controlling IOP
what are the 7 types of glaucoma tx?
- Cholinergics/miotics
- Beta-adrenergic receptor blockers
- Carbonic Anhydrase Inhibitors (CAI)
- Prostaglandins
- Adrenergic agonists
—eyedrops - Hyperosmotic agent
—pills - Laser Surgery
- Filter Surgery
—surgery
what is the action of a cholinergic/miotic, give 1 example of it
Effect exerted is through outflow
- contraction of ciliary muscle pulls open the pores of the
TM, thus increasing aqueous outflow. - Eg: Pilocarpine (Ocusert, Piloplex)
what is the action of BETA-ADRENERGIC RECEPTOR
BLOCKERS? what is 1 precaution of this drug? 4 examples?
Function: decreases aqueous production
precaution: amke sure px not using any existing beta blockers for heart condition.
- Timolol (Timoptic, Betimol)
- Levobunolol (Betagan)
- Carteolol (Ocupress)
- Betaxolol** (Betoptic)** B1 selective, less risk to px with pulmonary disease
NOTE: The remaining drugs are non-selective
2 side effects of beta blockers? advantage of betaxolol?
-Stinging sensation
* Potentially reduce heart rate
* caution with patients with heart problems, lung problems, diabetes, depression due to drug interaction
betaxolol:
Better Visual Field preservation
* Less systemic effects on circulation & respiratory system
what is the action of CARBONIC ANHYDRASE INHIBITORS
(CAI)? 2 examples?
- reduces aq secretion
- Usually used in combination with other anti-glaucoma drugs
- Eg: Dorzolamide (Trusopt)– eyedrops
Acetazolamide (Diamox)– Oral
3 side effects of CAIs eyedrops? 4 side effects of CAIs oral meds?
- Burning sensation
- Bitter taste
- Redness
Oral medication
- Depression
- Weight loss
- Kidney stones
- Tingling sensation
what is the action of prostalglandins? 3 examples?
Originally discovered in the eye as chemical mediators of
inflammation.
* However, it was later discovered that appropriate doses
of PGs can lower iop
- Eg: Latanoprost (Xalatan)
Travoprost (Travatan)
Bimatoprost (Lumigan)
how does prostaglandin decrease iop?
- IOP is reduced by increasing uveoscleral outflow.
- Precise mechanism is not known.
- Better compliance for prostaglandins as only require
1x/day instillation
what is uveoscleral outflow?
unconventional 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.
3 side effects of prostaglandins?
-Stinging & burning sensation
* eye colour change due to increased iris pigmentation
* lengthening of eyelashes
what is the action of ALPHA -ADRENERGIC AGONIST? 2 examples? mechanism of action?
alpha Receptors consist of
* a1
* a2
- In the eye, a2 are the predominant receptor in the iris & ciliary body.
- Stimulation of a2 receptors can decrease aqueous humour production.
Eg of a2 agonist drugs:
* Apraclonidine (Iopidine)
* Brimonidine (Alphagan)
mechanism of action not well defined
4 SIDE EFFECTS OF ALPHA ADRENERGIC AGONIST
- Blood shot eyes
- lid elevation
- dilated pupils
- Itching
how is hyperosmotic agents administered? who should take them? how do they work?
- 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
2 e.gs of hyperosmotic agents?
- Intravenous Agents
- More effective
- Eg: mannitol
- Oral Agents
- Eg: Glycerin (Osmoglyn)
