1. 1. Ocular hypotensive drugs and Antiglaucoma drugs
2. 2. Ocular hypertension Ocular hypertension is an eye pressure of greater than 21 mm Hg. An intraocular pressure of greater than 21 mm Hg is measured in one or both eyes.
3. 3. Normal eye pressure Eye pressure is measured in millimeters of mercury (mm Hg). Normal eye pressure ranges from 12-22 mm Hg, and eye pressure of greater than 22 mm Hg is considered higher than normal. When the IOP is higher than normal but the person does not show signs of glaucoma, this is referred to as ocular hypertension.
4. 4. Glaucoma A common eye condition in which the fluid pressure inside the eye rises to a level higher than healthy for that eye. If untreated, it may damage the optic nerve, causing the loss of vision or even blindness.
5. 5. Symptoms and sign of glaucoma Intense pain. Redness of the eye. Headache. Tender eye area. Seeing halos or 'rainbow-like' rings around lights. Loss of vision in one or both eyes that Progresses very quickly. Increase intraocular pressuse Glaucoma is characterized by progressive damage to the optic nerves
6. 6. Ocular hypotensive drugs Ocular hypotensive drugs are used to reduced the intraocular pressure.
7. 7. Ocular hypotensive drugs classification A..Prostaglandins analogues Latanoprost Travoprost Bimatoprost B..Beta-Adrenergic antagonist( b-blockers) Timolol Levobunolol Betaxolol Carteolol
8. 8. Ocular hypotensive drugs classification C.. Adrenergic agonist Apraclonidine Brimonidine D..Carbonic Anhydrase inhibitor Acetazolamide Methazolamide Dorzolamide Brinzolamide E..Cholinergic agonist(Miotics) Pilocarpine
9. 9. 1..Prostaglandins analogues: Prostaglandins analogues are first line treatment for most patient with ocular hypertension and open-angle glaucoma. Latanoprost the first commercially successful prostaglandins for clinical used in treatment of glaucoma.
10. 10. Latanoprost MOA: (Mechanism of action) It is a prostaglandin (PG)F2 analog. It is believed to reduced the intraocular pressure by increasing outflow of aqueous humor.
11. 11. Uses/Indication: Used in treatment of open-angle glaucoma or ocular hypertension in patient who are intolerant of other intraocular pressure lowering medication. Lanatoprost may be used alone or in combination with other antiglaucoma agents.
12. 12. Open-angle glaucoma, also called chronic glaucoma Closed angle glaucoma, also called acute glaucoma,
13. 13. Adverse effect Blurred vision Ocular burning Ocular pain Dry eyes Hyperlacrimation Photophobia Contraindication Hypersensitive to drug, if inflammation occur.
14. 14. 2..-blockers/-adrenergic antagonist Timolol: Timolol is a beta-adrenergic blocking agent. Non-selective, antagonize beta-1 and beta-2. Like other beta-adrenergic blocking agents, it mainly blocks the action of the sympathetic (adrenergic) nervous system.
15. 15. Mechanism of action Timolol causes a reduction of the pressure within the eye (intraocular pressure). This effect is may result from a reduction in production of the liquid (aqueous humor) within the eye. The precise mechanism of this effect is not known. The reduction in intraocular pressure reduces the risk of damage to the optic nerve and loss of vision in patients with glaucoma.
16. 16. Indication/use: Used for lowering intraocular pressure for treatment of glaucoma, acute-angle glaucoma.
17. 17. Contraindication: Hypersensitive to drug or class Asthma/bronchial problem Bradycardia Severe heart block Severe COPD Adverse effect Bradycardia Heart block Bronchospasm
18. 18. 3..Adrenergic Agonist Since early 1920s Epinephrine used as to reduced IOP.(non-selective adrenergic agonist) so currently used 2-receptor agonist are ,adrenergic agonist of choice for glaucoma. Apraclonidine Brimonidine
19. 19. Apraclonidine Mechanism of action: Selective -2 adrenoceptor agonist , derivative of antihypertensive agent clonidine. Apraclonodine lowers the intraocular pressure by decreasing aqueous production.
20. 20. 4..Carbonic Anhydrase inhibitor Acetazolamide Brinzolamide Dorzolamide Methoxazole
21. 21. Mechanism of action It reversibly blocks the enzyme carbonic anhydrase in the ciliary body and thus suppresses aqueous humor production. The Aquous fluid rich in sodium and bicarbonate ions is hyperosmotic as compared to plasma. Water is attracted to the posterior chamber as a result of osmosis and the high concentration of bicarbonate ions is diluted.
22. 22. Uses /Indication: 1..Used in treatment of all type of glaucoma. 2..Used in treatment of elevated IOP, Often reserved for short-term IOP reduction only. 3..produce an additional decrease in IOP ,when added to drug regimen ,including, Miotics, B- blockers and prostaglandins.
23. 23. Contraindication: Hypersensivity to drug. Pregnancy Severe obstructive pulmonary disease
24. 24. Side effect of Acetazolamide: Transient myopia Dermatitis Hypokalemia Fatigue Weight loss
25. 25. 5..Cholinergic Agonist(Miotics) Classification of cholinergic agonist Direct acting: Acetylcholine Methacholine Pilocarpine Carbachol
26. 26. Indirect acting (Cholinesterase inhibitor) (Reversible) Irreversible Physostigmine Ecothiophate Neostigmine Edrophonium Demacarium
27. 27. Mechanism of Action: Produce biological response similar to those of acetylcholine. these drugs also known as Parasympathomimetics or cholinomimetics. In clinical practice referred as Miotics.
28. 28. Direct Acting drugs: Activates cholinergic receptors directly at neuroeffector junctions of iris sphincter muscle and ciliary body. Indirect acting drugs: Exert their cholinergic effect by inhibiting cholinesterase and increase amount available at cholinergic receptors.
29. 29. Pilocarpine An alkaloid of natural plant origin. Pilocarpine is a direct acting cholinergic agonist.
30. 30. Mechanism of action Pilocarpine is a direct acting cholinergic parasympathomimetic agent which acts through direct stimulation of muscarinic receptors and smooth muscle such as the iris and secretory glands. Pilocarpine contracts the ciliary muscle, causing opening of the trabecular meshwork spaces to facilitate outflow of aqueous humor.
31. 31. Uses/indication Most useful miotic for management of acute angle closure glaucoma and many secondary glaucomas. Also used along with other agents. At high IOP of 60mmHg, topical beta- blockers,apraclonidine or systemic agents are indicated initially to bring pressuse below 50mmHg.
32. 32. Contraindication: Presence of cataract Patients younger than 40 year of age Asthma or history of asthma
33. 33. 6..Hyperosmotic agents These agents act by enhancing the osmotic pres- sure of plasma with respect to intraocular structures thereby setting an osmotic gradient. Consequently the fluid moves from the eye to hyperosmotic plasma of ocular blood vessels, thereby reducing the vitreous volume which is responsible for lowering of IOP.
34. 34. Hyperosmotic agents classification Include oral glycerin and isosorbide orally, mannitol and urea intravenously.
35. 35. Uses and indication The use of these drugs is currently limited to short term emergency situations such as acute angle closure glaucoma or pre- operative control of raised IOP.
36. 36. Hyperosmotic agents These drugs are usually for people with a severely high IOP that must be reduced immediately before permanent, irreversible damage occurs to the optic nerve. Hyperosmotic agents reduce IOP by lowering fluid volume in the eye.
37. 37. Side effects The side effects of these drugs include nausea, vomiting, diuresis, headache, diarrhea, chills and fever.