Anti glaucoma drugs
Download as PPTX, PDF•92 likes•31,902 views
The document outlines various anti-glaucoma drugs and their mechanisms of action aimed at reducing intraocular pressure (IOP) to prevent optic nerve damage. It details different types of medications including miotics, adrenergic agonists, beta-blockers, prostaglandin analogs, carbonic anhydrase inhibitors, and hyperosmotic agents, along with their indications, contraindications, and side effects. Combination therapies are discussed for both primary open-angle glaucoma and acute primary angle-closure glaucoma to optimize treatment effectiveness.
![I] PRIMARY OPEN ANGLE GLAUCOMA
(A) SINGLE DRUG THERAPY
1. Topical beta-blockers: DoC, 1st line
Timolol maleate, Betaxolol, Levobunolol, Carteolol
2. Latanoprost: 1st line
3. Dorzolamide: 2nd line
4. Pilocarpine: 2nd line
5. Adrenergic drugs: Dipivefrine hydrochloride (combined with beta-blockers
in patients where other drugs are contraindicated)
(B) COMBINATION TOPICAL THERAPY
If one drug is not effective, then a combination of two drugs—one drug
which decreases aqueous production (timolol or other betablocker, or
brimonidine or dorzolamide) and other drug which increases aqueous outflow
(latanoprost or brimonidine or pilocarpine) may be used.](https://image.slidesharecdn.com/anti-glaucomadrugs-180905153840/85/Anti-glaucoma-drugs-30-320.jpg)
![II] ACUTE PRIMARY ANGLE-CLOSURE GLAUCOMA
Medical therapy is instituted as an emergency and temporary measure before
the eye is ready for operation;
1. Systemic hyperosmotic agent intravenous mannitol (1 gm/kg body weight)
2. Acetazolamide 500 mg intravenous injection followed by 250 mg tablet
should be given 3 times a day.
3. Analgesics and anti-emetics
4. Pilocarpine eyedrops 2 percent pilocarpine should be administered every 30
minutes for 1-2 hours and then 6 hourly
5. Beta blocker eyedrops like 0.5 percent timolol maleate or 0.5 percent
betaxolol should also be administered twice a day to reduce the IOP.
6. Corticosteroid eyedrops like dexamethasone or betamethasone should be
administered 3-4 times a day to reduce the inflammation](https://image.slidesharecdn.com/anti-glaucomadrugs-180905153840/85/Anti-glaucoma-drugs-31-320.jpg)
Anti glaucoma drugs
- 1. ANTI-GLAUCOMA DRUGS DR.ANKITA MAHAPATRA 1ST YR PG, DEPT OF OPHTHALMOLOGY VSSIMSAR,BURLA
- 2. AIM OF GLAUCOMA TREATMENT MECHANISMS Reducing aqueous production in the ciliary body Promoting aqueous humour outflow through the trabecular meshwork Promoting aqueous humour outflow via the uveoscleral pathway IOP to levels that permit normal functioning of OPTIC NERVE and prevent further damage. Medications directed towards preventing neural cell loss (under investigation): MEMANTIN , BRIMONIDINE
- 3. INREASE TRABECULAR OUTFLOW: 1.MIOTICS(PILOCARPINE) 2.EPINEPHRINE,DIPIVEFRI NE 3.BIMATOPROST INCREASE UVEOSCLERAL OUTFLOW: 1.PROSTAGLANDIN (LATANOPROST) 2.ALPHA AGONISTS: EPINEPHRINE, DIPIVEFRINE BRIMONIDINE APRACLONIDINE DECREASE AQUEOUS OUTFLOW: 1.CAI : ACETAZOLAMIDE, DORZOLAMIDE 2.ALPHA AGONISTS: EPINEPHRINE, DIPIVEFRINE,CLONIDINE, BRIMONIDINE, APRACLONIDINE 3. BETA BLOCKERS: TIMOLOL, BETAXOLOL,LEVOBUNOLOL DRUGS:
- 4. PARASYMPATHOMIMETICS( CHOLINERGICS) MECHANISMOFACTION Contraction of the iris sphincter: Constricts the pupil(miosis) Mechanically moves away the iris from trabecular meshwork Contraction of the longitudinal fibers of the ciliary muscle Tension on the scleral spur(Opening the TRABECULAR MESHWORK) Facilitation aqueous outflow
- 5. PARASYMPATHOMIMETICS DIRECT ACTING Eg. PILOCARPINE INDIRCT ACTING OR CHOLINESTERASE INHIBITORS REVERSIBLE eg. PHYSOSTIGMINE IRRIVERSIBLE eg. ECHOTHIPHATE IODIDE, DEMECARIUM, DIISOPROPYL-FLUORO- PHOSPATE DUAL ACTION Eg.: CARBACHOL
- 7. PILOCARPINE : INDICATIONS : I. Long-term t/t of elevated IOP in patients having persistently occludable angle despite Laser iridotomy II. Pplx of Angle closure Glaucoma prior to Iridectomy. CONTRAINDICATIONS: Uveitic Glaucoma Blue eyes show maximal ocular hypotensive responses Darkly pigmented eyes demonstrate a relative resistance to IOP reduction Miotics better tolerated in Aphakic eye than in Phakic eye.
- 8. AVAILABLE PREPARATIONS: A. Eyedrops Available in 1%, 2% and 4% strengths. The onset of action:20 minutes Peaks in 2 hours Duration of effect :4-6 hours Prescribed every 6 or 8 hourly. B. Ocuserts Pilo-20 & Pilo-40 Changed once in a week. Pilo-20 used in patients controlled with 2 percent or less concentration of eyedrops pilo-40 in those requiring higher concentration of eyedrops. C. Pilocarpine gel (4%) Causes 18-25% fall in IOP.
- 9. CARBACHOL : INDICATIONS: alternative to pilocarpine in resistant or tolerant cases. PREPARATIONS: 0.75% , 3% DOSAGE: Duration of onset : 40 mins , Duration of effect : 12 hours 2-3 times/d OCULAR : Posterior synechiae, Keratitis Myopia, Retinal detachment Blurred vision, Cataract growth Miosis, Colour vision changes Brow ache , Epiphora Accommodative spasm SYSTEMIC: Increased sweating & salivation Urinary frequency Diarrhea Bronchospasm SIDE-EFFECTS:
- 10. SYMPATHOMIMETICS NONSELECTIVE ( alpha-1,2, beta-1,2 ) Eg. Epinephrine Dipivefrine Selective (alpha-1,2) Eg. Apraclonidine Selective (alpha-2) Eg. Brimonidine
- 12. 1.Epinephrine. Preparations: 0.5% , 1 % , 2% eyedrops. Dosage: The action starts within 1 hour and lasts up to 12-24 hrs 2. Dipivefrine (Propine or dipivalylepinephrine): Prodrug converted to epinephrine after its absorption into the eye. More lipophilic than epinephrine (corneal penetration increased by 17 times). Preparations:0.1 % eyedrops Dosage : Action and efficacy similar to 1% epinephrine. Twice daily
- 13. CLONIDINE : I. Decrease aqueous production II. Increase both trabecular and uveoscleral outflow (lesser extent) PREPARATIONS : 0.06% , 0.125 % 6-8 hrly SIDE EFFECTS : Conjunctival blanching Sedation Dry mouth Hypotension
- 14. APRACLONIDINE : I. Decrease aqueous production II. Decrease episcleral venous pressure III. Improves Trabecular outflow peak action : 2 hrs Duration of action : 12 hrs PREPARATIONS: 0.50 , 1 % 8hrly USES: Post- Laser trabeculoplasty & YAG laser iridotomy & posterior capsulotomy & cataract extraction SIDE EFFECTS : Allergic reaction Tachyphlaxis Conjunctival blanching Follicular conjunctivitis BRIMONIDINE : I. More selective alpha-2 action II. Less Tachyphylaxis ,Ocular allergic Reactions III. Not to be used in infants and young children, as risk of respi depression, Somnolence, Hypotension, seizure IV. Peak IOP reduction 26% ( 2 hours postdose) Caution recommended when using with MAOI, TCA
- 15. ADRENERGIC ANTAGONISTS(BETA BLOCKERS) NON-SELECTIVE (BETA-1,2 ) Eg. TIMOLOL, LEVOBUNOLOL, CARTELOL, METIPRANOLOL SELECTIVE (BETA-1) Eg. BETAXOLOL
- 16. BLOCKADE OF BETA RECEPTORS IN CILLIARY PROCESS (INHIBIT cAMP PRODUCTION) DECREASED RATE OF AQUEOUS PRODUCTION(20-50%) MECHANISM OF ACTION : Topical β-blockers reduce aqueous formation by 20% to 50% in awake humans. β-blockers are less effective during sleep Systemic absorption, leads to IOP lowering in untreated contralateral eye also.
- 17. TIMOLOL MALEATE 0.25-0.5% EYEDROPS- BD EYEGEL- OD LEVOBUNOLOL 0.25-0.5% LONGER HALF LIFE BETAXOLOL 0.25-0.5% *FEWER PULMONARY SIDEEFFECTS *INCREASE PERFUSION OF OPTIC NERVE HEAD CARTELOL *LESS EFFICACY *INTRINSIC SYMPATHOMIMETIC ACTIVITY, LESS BRADYCARDIA DRUGS: CARTELOL HAS LEAST EFFECT ON LIPID PROFILE
- 18. Beta-blockers have very good synergistic effect when combined with Miotics ; and are thus often used in combination in patients with POAG, unresponsive to the single drug. Dosing first thing in the morning preffered, to blunt an early morning pressure rise. ADDITIVE TO: Miotics Adrenergic agonists Carbonic anhydrase inhibitors PG Analogues Timolol and Latanoprost combination causes an additional IOP reduction of 13-37% Betaxolol is the beta blocker of choice In patients at risk for pulmonary diseases
- 19. CONTRAINDICATIONS: Bronchial Asthma Emphysema COPD Heart blocks, Congestive Heart Failure Cardiomyopathy. known drug allergies. OCULAR: STINGING LOCAL ANESTHESIA DRY EYE CONJUNCTIVAL HYPEREMIA SPK SYSTEMIC : BRONCHOSPASM( LESS WITH BETAXOLOL) BRADYCARDIA DECREASED CARDIAC OUTPUT HYPOTENSION DEPRESSION IMPOTENCE ALTERED LIPID PROFILE SIDE EFFECTS : Reduced glucose tolerance, masking of hypoglycemic signs and symptoms Occurs in Diabetics. Abrupt withdrawal of beta blockers can exacerbate Symptoms of Hyperthyroidism.
- 20. PROSTAGLANDIN ANALOGUES: STIMULATES PROSTANOID RECEPTOR IN CILIARY MUSCLE RELEASE OF MATRIX METALLOPROTEINASE DEGRADE THE EXTRACELLULAR MATRIX BETWEEN CILIARY MUSCLE BUNDLES REDUCTION OF HYDRAULIC RESISTANCE TO UVEOSCLERAL FLOW MECHANISM OF ACTION :
- 21. LATANOPROST 0.005% PRODRUG ACTIVATED DURING ITS PASSAGE THROUGH CORNEA LOWERS IOP BY 25-30% ADDITIVE EFECT WITH TIMOLOL BIMATOPROST 0.01%, 0.03% CAUSES PIGMENTATION OF SKIN OTHERS: TRAVOPROST 0.004% TAFLUPROST 0.0015% (FIRST PRESERVATIVE FREE PG ANALOGUE) UNOPROSTONE 0.12% DRUGS: UNOPROSTONE increases retinal blood flow
- 22. ADVANTAGES: • Once daily dosing • Lack of cardiopulmonary side effect • Additive to other anti-glaucoma medications SIDE EFFECTS: Conjunctival hyperaemia SPK CME Anterior uveitis Blurred vision CONTRAINDICATIONS: Ocular infection Inflammation Increased pigmentation of iris, lashes Hypertrichosis Trichiasis Districhiasis Hair growth around eye
- 23. CARBONIC ANHYDRASE INHIBITOR INHIBIT CARBONIC ANHYDRASE IN CILLIARY PROCESSES REDUCTION IN AQUEOUS HUMOR PRODUCTION IOP DECREASES MECHANISM OF ACTION: Potent and most commonly used Systemic Anti-Glaucoma drugs >90% of ciliary enzyme activity must be abolished to decrease aqueous production and IOP
- 24. SYSTEMIC ACETAZOLAMIDE METHAZOLAMIDE DICHLORPHENAMIDE ETHOXZOLAMIDE TOPICAL DORZOLAMIDE BRINZOLAMIDE LODOXAMIDE DRUGS:
- 25. ACETAZOLAMIDE: Reduces aqueous production by 30-40% USE: control of very high IOP in Acute angle closer Refusal of surgery DOSAGE: 250mg tabs 6hrly SR 500mg BD 500mg IV lowers IOP within 20 minutes SIDE EFFECTS (Dose related): Altered taste loss of appetite Paraesthesia of hands, feet Sulfa allergy Hypokalaemia Metabolic acidosis Renal stones Blood dyscrasias ACETAZOLAMIDE Not metabolized, excreted in urine. Can be given in hepatic failure. METHAZOLAMIDE Metabolized by liver. Decrease risk of systemic adverse effects
- 26. DORZOLAMIDE: • Topical agent • PREPARATION: 2% • FALL IN IOP: 13-24% • SIDE EFFECTS: Punctate keratitis Bitter taste allergic reaction Transient burning d/t decrease in ph BRINZOLAMIDE: 1% preparations Suspension causes white deposits in tear film Eyes with compromised endothelial function, are at risk of corneal decompensation.
- 27. HYPEROSMOTICS: IV: Mannitol ORAL: Glycerol Increase blood osmolality Osmotic gradient created between blood and vitreous Drawing water from Vitreous cavity Decrease IOP MECHANISM OF ACTION :
- 28. MANNITOL: 20% 0.5- 2.0 g/kg Body weight s/e: IOP rebound Increased aqueous flare headache Mental confusion Backache CHF, MI Subdural, Subarachnoid haemorrhage Larger the dose, more rapid the administration, greater decrease in IOP. Rarely administered for longer duration, cause effects are transient, result of rapid reequilibration of Osmotic gradient. Less effective overtime, rebound increase in IOP may occur. GLYCEROL: • Concentration 50% • 1-1.5 g/kg dosing • It precipitates hyperglycaemia, Ketoacidosis in DIABETICS Hyperosmotics are contraindicated in patients with renal failure or on dialysis
- 29. FIXED COMBINATIONS: COMPOUNDS CONCENTRATION TIMOLOL/BRINZOLAMIDE 0.5%/1% TIMOLOL/DORZOLAMIDE 0.5%/2% TIMOLOL/LATANOPROST 0.5%/ 0.005% TIMOLOL/TROVAPROST 0.5%/ 0.004% TIMOLOL/BIMATOPROST 0.5%/0.03% TIMOLOL/BRIMONIDINE TARTARATE 0.5%/ 0.2% DOSING BD BD OD, AT NIGHT TIME OD, AT NIGHT TIME OD, AT NIGHT TIME BD
- 30. I] PRIMARY OPEN ANGLE GLAUCOMA (A) SINGLE DRUG THERAPY 1. Topical beta-blockers: DoC, 1st line Timolol maleate, Betaxolol, Levobunolol, Carteolol 2. Latanoprost: 1st line 3. Dorzolamide: 2nd line 4. Pilocarpine: 2nd line 5. Adrenergic drugs: Dipivefrine hydrochloride (combined with beta-blockers in patients where other drugs are contraindicated) (B) COMBINATION TOPICAL THERAPY If one drug is not effective, then a combination of two drugs—one drug which decreases aqueous production (timolol or other betablocker, or brimonidine or dorzolamide) and other drug which increases aqueous outflow (latanoprost or brimonidine or pilocarpine) may be used.
- 31. II] ACUTE PRIMARY ANGLE-CLOSURE GLAUCOMA Medical therapy is instituted as an emergency and temporary measure before the eye is ready for operation; 1. Systemic hyperosmotic agent intravenous mannitol (1 gm/kg body weight) 2. Acetazolamide 500 mg intravenous injection followed by 250 mg tablet should be given 3 times a day. 3. Analgesics and anti-emetics 4. Pilocarpine eyedrops 2 percent pilocarpine should be administered every 30 minutes for 1-2 hours and then 6 hourly 5. Beta blocker eyedrops like 0.5 percent timolol maleate or 0.5 percent betaxolol should also be administered twice a day to reduce the IOP. 6. Corticosteroid eyedrops like dexamethasone or betamethasone should be administered 3-4 times a day to reduce the inflammation