Ocular Phys Drugs & Sx (Midterm 2)

Netarsudil

Rho Kinase Inhibitor

Promotes TM relaxation which increases AH outflow = decrease in IOP

Vasodilation of Episcleral veins = increase AH outflow = decrease in IOP

Side effect: Red eyes

Give the mechanism of Netarsudil & side effect(s)

Selective Laser Trabeculoplasty (SLT)

Surgery that elicits selective photothermolysis resulting in increased AH outflow

Laser sent into the pigmented TM --> Pigmented TM soaks up the energy from the laser --> release of cytokines (d/t absorbed energy from laser causing slight amount of inflam) --> macrophages recruited & debris cleared away --> promotion of TM & endothelial cells to proliferate

Give the mechanism of SLT therapy

Latanoprostene Bunod (Vyzulta)

Glaucoma drug that is used to increase outflow and oppose increased IOP

Contains two active forms

Latanoprost acid & Nitric oxide

What are the 2 active forms of latanoprostene bunod?

Latanoprost acid stimulates vasodilation & Nitric oxide relaxes the TM increasing outflow AND also causing vasodilation --> results in decreased IOP & increased AH outflow

Mechanism of latanoprostene bunod

Dexamethasone

Glucocorticoid (mentioned in class for Angle ppt)

* Alters the make-up of the TM

* INHIBITS prostaglandin synthesis

* REDUCTION of phagocytic and extracellular protease activity

* Changes gene expression (introduces gene MYOC) --> increases production of myocylin --> builds up as debris in the TM --> decreased phagocytic activity unable to clear away --> poor AH outflow

OVERALL: Increases IOP

Glucocorticoid mechanism

Brimonidine

Alpha-2 agonist

Activation of alpha-2 receptors --> reuptake of NorEpi -> reduces release of NorEpi -> reduction of cAMP via adenylate cyclase ==> DECREASES IOP

Enhances unconventional outflow (with an unsure mechanism)

Mechanisms of Brimonidine

Latanoprost (Xalatan)

Prostaglandin analog

Results in vasodilation = increasing outflow = Decreasing IOP

can disrupt Blood:aqueous barrier

Mechanism of Latanoprost

Pilocarpine (Vuity)

Parasympathomimetic drug first used on glaucoma patients, but now has gained popularity with the presbyopic community

Stimulation of M3 ciliary body muscle receptors = contraction of the CB muscle

Also results in miosis (increasing Depth of Field)

With contraction of CB muscle = increases outflow via opening of anatomical angle = drop in IOP

Side effect = Retinal detachment

*can also affect blood:aqueous barrier

Mechanism of Pilocarpine

& side effect(s)

Atropine

Cycloplegic drop that takes 6-24 hours for onset & lasts for 10-15 days

Used to break-up synechiae in uveitis patients

Cyclopentolate

Cycloplegic drop that takes 30-45 minutes for onset & lasts for 12-24 hours

Used on children d/t high affects of knocking out accommodation

Tropicamide

Cycloplegic drop that takes 20-30 minutes for onset & lasts 4-10 hours

Most used in clinic d/t less long-lasting effects

Phenylnephrine

Sympathomimetic drop often used in conjunction with a parasympatholytic drop in clinic

Dorzolamide & Brinzolamide

Carbonic anhydrase inhibitors --> used to treat glaucoma

Decreases conc. of HCO3- ions, Na+ ions & Cl- ions in the pigmented & non-pigmented epithelium --> results in less ions pulling water with them out into the aqueous humor ==> Drop in IOP

*works independently of ANS (so still functions at night)

Mechanism of Dorzolamide & Brinzolamide

Timolol & Levobunolol

B-blocker (non-specific) used to treat glaucoma

Blockade of Beta-1 and Beta-2 receptors (more Beta-1s) -> inhibition of cAMP synthesis -> decreased rate of AH production ==> DECREASES IOP

Utilizes ANS, so only really functional during the day

Mechanism of action for Timolol & Levobunolol

Laser Peripheral Iridotomy

Laser procedure used to equalize the pressure in the anterior & posterior chamber of patients with primary angle-closure glaucoma

aims for cypts near the iris root

Aceclinidine (Vizz)

A cholinergic agonist (parasympathomimetic) that is more selective to stimulating iris sphincter m. > Ciliary body m.

Stimulation of M3 receptors on iris sphincter m. > Ciliary body m. --> smaller pupil resulting in a smaller blur circle on the retina ==> Increases Depth of focus

*MUCH less risk for a retinal detachment

Side Effect = Red eye

Mechanism of Aceclinidine & side effect(s)