Glaucoma Pharmacological Management

Ans. Dipivefrine

Ans. D 

Pilocarpine as eye drops it is used to manage angle closure glaucoma until surgery can be performed, ocular hypertension, primary open angle glaucoma, and to bring about constriction of the pupil following its dilation.

Pilocarpine contracts the ciliary muscle, causing increased tension on the scleral spur and opening of the trabecular meshwork spaces to facilitate outflow of aqueous humor. Outflow resistance is reduced, lowering intraocular pressure (IOP).

Ans. Sphincter pupillae muscle

Ans. Pigmented pupillary cyst

Ans. C i.e. Timolol maleate

Contraindications of Timolol maleate

• Bronchial asthma;
• A history of bronchial asthma;
• Severe chronic obstructive pulmonary disease
• Sinus bradycardia;
• Second or third degree atrioventricular block;
• Overt cardiac failure
• Cardiogenic shock;
• Hypersensitivity to any component of this product.

Ans. A i.e. Retrobulbar injection of steroid

Ans. B: Atropine

Anticholinergic drugs (atropine 1%, homatropine2%) dilates the pupil

In a patient above 60 years of age having hypermetropia and a shallow anterior chamber, mydriasis may precipitate acute angle closure glaucoma

Ans. is ‘b’ i.e., Beta – blockers

Ans. is ‘d’ i.e., Brimonidine

Ans. is ‘d’ i.e., Oral acetazolamide

Treatment of POAG (Primary open angle glaucoma) 

Following treatment options are available for POAG :

Medical therapy :- Total medical therapy is the treatment of choice for POAG. Topical 13-blockers (Timolol, Betoxalol, Levobunolol, carteolol) are the drugs of choice. Topical prostaglandin analogues (Latanoprost, bimatoprost, travoprost) are the second choice drugs. Other topical drugs for POAG are:- LI Alpha agonists (non – selective : epinephrine, dipivefrine; and Selective – a₂: apraclonidine, brimonidine)

Carbonic anhydrase inhibitors (Dorzalamide, brinzolamide)

Cholinomimetic drugs (Pilocarpine, physostigmine, echothiophate, carbachol) Pilocarpire has several drawbacks, therefore, is being considered as an adjunctive therapy only as a last resort.

Approach to treatment of POAG

• Start monotherapy with topical P-blocker or latanoprost.
• If target IOT is not attained either change over to the alternative drug or use both the above concurrently.
• Brimonidine/dorazolamide/dipivefrine are used only when there are contraindications to PG analogues or 13-blockers.
• Topical miotics and oral acetazolamide are added only as the last resort.
• Systemic therapy is considered only as a last resort. Drugs used for systemic therapy are :- (i) Carbonic anhydrase inhibitors (Acetazolamide, Dichlorphenamide, methazolamide), (ii) Hyperosmotic agents (mannitol, glycerol).

Ans. is ‘a’ i.e., Decreased aqueous secretion

Ans.B. Increasing uveoscleral outflow

• Latanoprost is an analog of prostaglandin F2a that increases uveoscleral outflow and induces miosis.

Antiglaucoma Drugs: Mechanism of Lowering Intraocular Pressure (IOP):
Drugs that increase trabecular outflow

•  Miotics (e.g., pilocarpine)
•  Epinephrine, dipivefrine
•  Bimatoprost

Drugs that increase uveoscleral outflow

•  Prostaglandins (latanoprost)
•  Epinephrine, dipivefrine
•  Brimonidine
• Apraclonidine

Drugs that decrease aqueous production

•  Carbonic anhydrase inhibitors (e.g., acetazolamide, dorzolamide)
•  Alpha receptor stimulators in ciliary process (e.g., epinephrine, dipivefrine, clonidine, brimonidine, apraclonidine)
• Beta-blockers

Hyperosmotic agents – (e.g., glycerol, mannitol, urea).

Ans. is ‘c’ i.e., Alpha agonist

Drug of choice for initial treatment of open angle glaucoma is either an topical β-blocker or topical PG analogue (latanoprost)

It target IOT is not attained either change over to alternative drug or use both concurrently.

In refractory cases (who are not responding to (3-blockers and PG analogues), topical α-agonist (Brimozidine) or topical carbonic anhydrase inhibitor (dorazolamide) is added.

It target IOT is still not attained, laser trabeculoplasty is considered.

Ans. is ‘a’ i.e., I.V. Mannitol

Treatment of angle closure glaucoma

• Definitive treatment (treatment of choice) is surgery. However, intially drugs are used to decrease KW during an acute attack. Approach of treatment is as follows:-
• Start i.v. mannitol or i.v. acetazolamide
• When IOT starts falling, start topical pilocarpine or β-blocker (timolol).
• Apraclonidine/latanoprost may be added.
• Once IOT is reduced, surgery is done.
• Topical pilocarpine 2% is the preferred antiglaucomatous drug.
• After control of IOP, Laser (Nd : YAG) peripheral irodotomy is the definitive management of choice. If laser is not available surgical peripheral iridectomy is the procedure of choice. Other surgical procedures used are filteration surgeries (like trabeculectomy, deep sclerotomy, Viscoanulostomy).
• Symptomatic treatment during an attack also includes analgesics, antiemetic and topical corticosteroids to reduce inflammation. Mydriatics (e.g. atropine) are contraindicated as they precipitate glaucoma.
• PACG is a bilateral disease, the fellow eye is at risk of developing an acute attack in 50% cases in future. Therefore a prophylactic peripheral laser iridotomy should be performed in the fellow eye.

Ans. c. Levobunolol

• Brimonidine, dorzolamide and prostaglandin are topical anti-glaucoma drugs. These drugs do not have systemic side effects, while levobunolol (beta-blocker) is systemic anti-glaucoma drug given orally, having systemic side effects. That is why in patients with glaucoma treated with systemic beta blockers, levobunolol may add on the side effects of beta-blockers, hence avoided in the above mentioned patient.

Topical Anti-glaucoma Drugs

Adrenergic agonist

• Non-selective: Epinephrine, Dipivefrine
• Alpha2-selective: Apraclonidine, Brimonidine

Adrenergic antagonist

• Beta—blocker (Non-selective): Timolol, Levobunolol, Carteolol, Metipranolol, Adapralol
• Betal-blocker: Betaxolol

Miotics (direct parasympatomimetics)

• Pilocarpine, Physostigmine
• Ecothiophate, Carbachol, Demacarium

Prostaglandin analogues

• Latanoprost

Carbonic anhydrase inhibitors

Dorzolamide

Systemic Antiglaucoma Drugs

Carbonic anhydrase inhibitors

• Acetazolamide
• Dichlorphenamide
• Methazolamide

Hyperosmotic agents

• Mannitol
• Glycerol

Ans. is ‘c’ i.e., Brimonidine 

Important systemic side effects of topical agents

• n-blockers : Bronchospasm, bradycardia, .cardiac output, hypotension, depression, impotence, altered lipid profile (hypercholesterolemia).
• Sympathomimetics
• Non selective (Dipivefrine, epinephrine) :- Hypertension, arrhythmias
• Selective a-2 (Brimonidine):- Drowsiness, fatigue, BP changes
• Selective a-1 & a2 (Apraclonidine) :- Drowsiness, Headache, fatigue
• Chlinomimetics (Pilocarpine) :- Sweating, salivation, urinary frequency, diarrhea, bronchospasm.
• Carbonic anhydrase inhibitors (Dorzolamide, brinzolamide) :- Bitter taste, headache, asthenia, renal calculi.
• Prostaglandin analogues (Latanoprost) :- Headache, symptoms of URTI.

. Ans. is ‘c’ i.e., Acetazolamide 

Timolol is one of the first-line agents used in the treatment of primary open-angle glaucoma (POAG)
First-line agents:

•  Topical beta-blockers such as timolol, betaxolol, and levobunolol 
•  Selective alpha 2 adrenergic agonist brimonidine
•  Prostaglandin analogues such as latanoprost and bimatoprost

Adjunctive therapy: Carbonic anhydrase inhibitors
Laser trabeculoplasty: In cases where intraocular pressure (IOP) is uncontrolled despite maximal tolerated medical therapy.

Note: Since prostaglandin (PG) analogues are not included in the options, the next best option to choose is timolol.

• Historically, beta-blockers were the most common first-line agents used in the medical treatment of POAG.
• However, with an increase in our experience with newer agents, specifically the prostaglandin analogues that facilitate outflow, they were recognized as being more efficacious in lowering IOP and systemically safer than beta-blockers.
• As a result, now they are the first-line agents in glaucoma treatment.

Ans. is ‘a’ i.e., Produces no miosis 

Advantages of topical n-blockers (timolol) over miotics (pilocarpinel

No change in pupil size (no miosis)              →       No fluctuation in I.O.T.

No induced myopia                                     →       Convenient once/twice daily applications

No ciliary spasm (no spasm of accomodation)  →    Few systemic side effects.