classification of medical treatment in management of glaucoma and its side effects

1. Pharmacotherapy of glaucoma
Dr. Samten Dorji

2. Outline
• Introduction
• Pharmacotherapy
• Classification and mechanism of action
• Summary

3. Introduction
• Glaucoma is a group of ocular disorders with
multifacorial aetiology united by a clinically
characterstic intraocular pressure-associated
optic neuropathy.

4. Pharmacotherapy
• Prevention or modification of risk factor
Intraocular pressure

5. Classification
Topical drugs
• Cholinergic agents
• Adrenergic agonists
• Beta blockers
• Prostaglandin analogs
• Carbonic anhydrase
inhibitors
Systemic drugs
• Carbonic anhydrase
inhibitors
• Osmotic agents

6. Mechanism of action
• Decrease aqueous production in the ciliary
body
• Increase aqueous humor outflow through the
trabecular meshwork and uveoscleral pathway

7. Cholinergic drugs
Direct acting
miotic
Cholinesterase
inhibitors

8. Pilocarpine (direct acting)
• Relieves the pupillary block in angle closure
glaucoma
• Increases the trabecular outflow
• 0.5-0.4%
• Last for 4-8 hours
• superficial punctate keratitis, ciliary muscle
spasm which can lead to browache, induced
myopia, miosis, possible retinal detachments,
progression of cataract and corneal endothelial
toxicity

9. Cholinesterase inhibitors
• Short acting-Physostigmine, neostigmine and
demecarium
• Long acting- ecothiophate and isofluorophate
• angle closure and open angle glaucoma
• profound muscle weakness and cystoid
macular edema

10. Adrenergic agonist
• Decreases aqueous humor production and
increases trabecular outflow
• May last upto 72 hours
• Conjunctival decongestion and transient
mydriasis. Systemic hypertension, stinging,
browache, conjunctival hyperemia,
adenochrome deposits and allergic lid
reactions
Adrenaline

11. Brimonidine
• First line agent
• Highly selective alpha 2 receptor agonist
• 0.2%
• suppressing the rate of aqueous humor flow
and enhancing uveoscleral flow

12. Beta adrenergic antagonist(timolol)
• Inhibits both beta 1 and beta 2 adrenergic activity
• First line agent
• 0.25% or 0.5%
• Duration of action exceeds 7 hours
• localized irritation of the corneal epithelium can
result in blurred vision, conjunctival hyperemia,
superficial punctate keratopathy and dry eye
symptoms
• Short term escape and long term drift

13. Prostaglandin analogues
• Mediated by prostanoid receptors
• Enhancing uveoscleral outflow
• 0.005% and instilled at night
• Duration of action 24 hours
• Mild conjunctival hyperemia, punctate
corneal erosions and lengthening and
thickening of eyelashes
Latanaprost

14. Carbonic anhydrase inhibitors
• It reversibly blocks the enzyme carbonic
anhydrase in the ciliary body and thus
suppresses aqueous humor production
• 125-250mg four times daily
• Gastrointestinal upset, myopia, pulmonary
failure, renal stones, aplastic anaemia,
metabolic acidosis, hypersensitivity reactions
and peripheral neuropathy
Acetazolamide

15. Dorzolamide
• Topical ophthalmic use
• It penetrates cornea, inhibits carbonic
anhydrase-II in the ciliary body, slows the
production of local bicarbonates and thus
decreases sodium and fluid transport which in
turn reduces the secretion of aqueous humor
• 2% twice daily
• irreversible corneal edema in patients having a
compromised endothelium

16. Osmotic agents
• Enhance the osmotic pressure of plasma
• Mannitol, glycerol and urea
• Acute angle closure glaucoma and pre
operative raised IOP
• nausea, vomiting, diuresis, headache,
diarrhea, chills and fever

17. Summary

18. Thank you