Pharm - Glaucoma Flashcards
Carbachol
Activates ACh receptor
Increase outflow of aqueous humor via contraction of ciliary muscle and opening of trabecular meshwork
Miosis and cylcospasm
Exhibits a strong nicotinic activity, may cause widespread autonomic disturbances if it gets into systemic circulation
Pilocarpine
ACh receptor agonist
USED IN EMERGENCIES
Increase outflow of aqueous humor via contraction of ciliary muscle and opening of trabecular meshwork
Miosis and cyclospasm
May cause paradoxical hypertension and tachycardia
Physostigmine
AChE inhibitor
Increase outflow of aqueous humor via contraction of ciliary muscle and opening of trabecular meshwork
crosses the BBB, can cause seizures and abnormal defecation
Ecothiophate
AChE Inhbitor
Increase outflow of aqueous humor via contraction of ciliary muscle and opening of trabecular meshwork
Can cause night blindness and frontal headache
Timolol
non-selective beta blocker
Decreases aqueuous humor production by inhibiting ciliary process epithelium
Chronic open angle Glaucoma
Cold extremities, bradycardia, hypotension, fatigue are common with use of most beta blockers
bradycardia, confusion, blurred vision, dry eyes, hallucination, bronchospasm
Carteolol
non-selective beta blocker
Decreases aqueuous humor production by inhibiting ciliary process epithelium
Chronic open angle Glaucoma
Cold extremities, bradycardia, hypotension, fatigue are common with use of most beta blockers
insomnia, bronchospasm
Betaxolol
Selective beta 1 blocker
Decreases aqueuous humor production by inhibiting ciliary process epithelium
Chronic open angle Glaucoma
Cold extremities, bradycardia, hypotension, fatigue are common with use of most beta blockers
AV block, myocardial infarct
Beta blockers usually decrease the force and contraction and thus decrease the metabolic demand of the heart but betaxolol is paradoxal in that it can cause MI and AV Block
latanoprost
Prostaglandin PGF2α analog, lowers intraocular pressure
Increase the uveoscleral outflow of the aqueous humor
Darkens color of the iris (browning)
Macular retinal edema
bimatoprost
Prostaglandin PGF2α analog, lowers intraocular pressure
Increase the trabecular meshwork outflow of the aqueous humor
Darkens color of the iris (browning)
Macular retinal edema
Conjunctival hyperemia
travoprost
Prostaglandin PGF2α analog, lowers intraocular pressure
Increase the trabecular meshwork outflow of the aqueous humor
Darkens color of the iris (browning)
Macular retinal edema
Conjunctival hyperemia
Acetazolamide
Carbonic Anhydrase Inhibitors
Decrease aqueous humor production secondary to a decrease in HCO3- due to inhibition of carbonic anhydrase II in the eye.
Electrolyte imbalance
Metabolic acidosis
Urolithiasis
Agranulocytosis, aplastic anemia, thrombocytopenia (acetazolamide)
Brinzolamide
Carbonic Anhydrase Inhibitors
Decrease aqueous humor production secondary to a decrease in HCO3- due to inhibition of carbonic anhydrase II in the eye.
Electrolyte imbalance
Metabolic acidosis
Urolithiasis
Dorzolamide
Carbonic Anhydrase Inhibitors
Decrease aqueous humor production secondary to a decrease in HCO3- due to inhibition of carbonic anhydrase II in the eye.
Electrolyte imbalance
Metabolic acidosis
Urolithiasis
Immune hypersensitivity reactions
Burning sensation in the eye, visual discomfort
Apraclonidine
Alpha-2 Selective Agonists
Decrease production (decrease cAMP) and increase outflow of aqueous humor → decrease ocular pressure
Lower ocular pressure associated with eye surgery. Given pre and post surgery
May include irregular heart rate, fatigue, dry mouth, red, itchy or swollen eyes
Depression, dizziness and chest pain may occur with apraclonidine
Brimonidine
Alpha-2 Selective Agonists
Decrease production (decrease cAMP) and increase outflow of aqueous humor at uveoscleral outflow → decrease ocular pressure
Open angle glaucoma and ocular hypertension
May include irregular heart rate, fatigue, dry mouth, red, itchy or swollen eyes
Alpha-2 selective agonist
Alpha 2 agonists, through the activation of a G protein-coupled receptor, inhibit the activity of adenylate cyclase. This reduces cAMP and hence aqueous humour production by the ciliary body.
Peripheral alpha 2 agonist activity results in vasoconstriction of blood vessels (as opposed to central alpha 2 agonist activity that decreases sympathetic tone, as can be seen by the medication clonidine). This vasoconstriction may explain the acute reduction in aqueous humor flow. The increased uveoscleral outflow from prolonged use may be explained by increased prostaglandin release due to alpha adrenergic stimulation. This may lead to relaxed ciliary muscle and increased uveoscleral outflow.[
Dipivefrin
Non-Selective Adrenergic Agonists
Decrease aqueous humor production due to vasoconstriction and decrease blood flow to ciliary bodies (epinephrine)
Dipivefrin is a pro-drug, hydrolyzed to epinephrine within the eye
Burining sensation in the eye, follicular conjunctiva
Mydriasis, stinging, not be used in close-angle glaucoma
Epinephrine
Non-Selective Adrenergic Agonists
Decrease aqueous humor production due to vasoconstriction and decrease blood flow to ciliary bodies (epinephrine)
Mydriasis, stinging, not be used in close-angle glaucoma
Carbonic Anhhydrase Inhibitors
When used to treat glaucoma, CAIs inhibits production of HCO3-. In health, it is the production of HCO3- which draws Na+ into the eye; water follows by osmosis to form the aqueous humour. In glaucoma treatment, the goal is often to reduce the intraocular pressure and acetazolamide does this by reducing production of aqueous humour.
