Glaucoma Flashcards
Types of Glaucoma
Primary (POAG vs PCAG)
Secondary
Primary glaucoma
No underlying cause identified
Further broken down into
- Primary Open Angle Glaucoma (POAG)
- Primary Angle closure Glaucoma (PACG)
Secondary Glaucoma
Due to identifiable cause: HTN, diabetes, Trauma
Primary Open Angle Glaucoma
Most common
Angle between Iris and cornea= open and normal
Increased IOP from resistance to drainage of AH via trabecular network
Primary Angle Closure glaucoma
Angle between iris and cornea narrows—> prevents drainage of aqueous fluid
Acute PACG
Sudden rise in IOP ( ≥ 30mmHg)
Medical emergency that can result in vision loss
Sx of acute PACG
Pain
Headache
Nausea
Vomiting
Blurry vision
Halos around lights
Chronic PACG
Asymptomatic
Gradual progression of optic nerve damage
Risk factors for POAG (4)
FmDx
Age >40
Race—> AA
Elevated IOP (>21mmHg= increased risk)
Medications that exacerbate or induce glaucoma (5)
Glucocorticoids
Anticholinergics
TCAs
First Gen Anhistamines
Decongestants
How do medications with an antcholinergic effect cause glaucoma?
Anticholinergics produce pupillary dilation—> angle between iris and cornea narrow—> increased IOP
What population should avoid use of medications with anticholinergic effects due to the risk of glaucoma?
Patients with PACG
What Anticholinergics (specifically) induce glaucoma?
Scopolamine
Benztropine
Trihexphenidyl
Treatment of choice for Chronic PACG
Laser Iridotomy
Treatment options for glaucoma
Pharmacotherapy
Laser therapy
Surgical intervention
Laser Iridotomy—> 1st line chronic PACG
When may the target IOP be lower?
When the patient has disease progression of glaucoma despite IOP lowering
T/F: decreases IOP treats/cures glaucoma
False
Decreasing IOP helps prevent and slow progression
Goal of glaucoma treatment
Decrease IOP to help prevent/reduce disease progression
How can medications accomplish reduction of IOP?
Decreasing aqueous fluid production
Increasing Aqueous fluid outflow
What is the initial goal for IOP reduction?
20-50%
Agents that DECREASE FLUID PRODUCTION
Β Blockers- 1st line
𝛼 Adrenergic Agonists - 2nd line
Carbonic Anhydrase inhibitors
— topical- 2nd line
— systemic- 3rd line
Meds that decrease fluid production MNEUMONIC
BAC T2S3
Agents that INCREASE FLUID OUTFLOW
Prostaglandin Analogs (PG)- 1st line
𝛼 2 adrenergic agonists- 2nd line
Cholinergic agonists- 3rd line
Rho Kinase Inhibitors (ROCK inhibitors)
What is the first line agent in DECREASING AQUEOUS FLUID PRODUCTION?
Β Blockers
What is first line agent for increasing fluid outflow?
Prostaglandin Analogs (PG)
Agents that increase fluid outflow MNEUMONIC
PACR
Prostaglandin Analog MOA
Reduce IOP by increasing outflow of of AH via UVEOSCLERAL ROUTE
Results in remodeling of the extracellular matrix—> increasing outflow
How long does it take to get a maximum IOP reduction with prostaglandin analogs?
3-5 weeks
Approximate IOP reduction provided by Prostaglandin Analogs
25-35%
Why are Prostaglandin analogs considered 1st line therapy for increasing fluid outflow?
Once daily formulation
High efficacy
Low side effect profile
Side effects of Prostaglandin Analogs
H2IREM
Hyperemia
Hyperpigmentation- iris, lid, lashes
Increase length and # of lashes
Reactivaiton of Herpes keratitis
Eye irritation
Macular edema
What color does the eye pigmentation change to when using prostaglandin analogs? Reversible or permanent?
Brown
Reversible
What will happen to the length and # of eyelashes following discontinuation of prostaglandin analogs?
Revert back to normal
What population should we avoid giving prostaglandin analogs to? Why?
Those with active IO inflammation—> can worsen
What are the 4 prostaglandin analogs?
Bimatoprost
Latanoprost
Travoprost
Tafluprost
Bimatoprost is also available as LATISSE which is used to treat what?
Hypotrichiosis (for eyelash growth)
PGs have many __________ side effects but little ________effects
Local
Systemic
Β Blocker MOA for glaucoma
Suppress the aqueous production in ciliary body epithelium—> reduce IOP
Β Blockers have increased _____________ side effects but well tolerated _____________ effects
Systemic
Local
How much IOP reduction do Β blockers provide?
20-25%
What is the ONLY cardioselective opthalmic BB?
Betaxolol
What are the advantages of Betaxolol?
Fewer pulmonary sie effects
Not contraindicated in patients with bronchospastic disease ( still use caution)
What are the non-selective opthalamic β blockers?
Timolol
Cartelol
Levobunolol
Metipranolol
Topical β blockers reach systemic circulation via what 2 routes?
Lacrimal ducts (which go into nasal mucosa)
Conjunctival vessels
T/F: systemic effects of topical BB are comparable to those of oral BB
False:
SE= lower than oral
Topical BB therapy can effect what systems?
CV
Respiratory
CNS
Metabolic
Topical BB are known to cause ____________ in frail elders and individuals with cardiac disease
Bradycardia
Approximately 8-% of topical BB is symmetrically absorbed, avoiding ___________
First pass metabolism
Timolol is contraindicated especially in elderly due to what systemic effects?
Symptomatic bradycardia
Conduction disorders in the heart
Orthostatic hypotension
Syncope
Falls
Side effects of opthalamic BBs
Bradycardia
Bronchospasm (non-selective)
Hypotension
Eye irritation/dry eye
What are the 5 topical BBs?
Betaxolol
Carteolol
Levobunolol
Metripranolol
Timolol
𝛼-2 adrenergic agonists MOA
Reduce IOP by decreasing aqueous production
What additional MOA does Brimonidine have?
Increases uveoscleral outflow
What are the 2 𝛼-2 adrenergic agonists?
Apraclonidine
Brimonidine
Indication of use for Apraclonidine
Indicated for short term-add on treatment while awaiting surgery
Loses effect long-term
why is Brimonidine 2nd line?
Due to undesireable side effects
What are the indications of use for 𝛼-2 adrenergic agonists?
Contraindication to BB or PG analogs
Additional lower of IOP
𝛼-2 analog agonist side effects
Allergic conjunctivits
Hypotension
Dry mouth
Sedation
What is the frequent side effect of Brimonidine that often causes treatment discontinuation?
Allergic conjunctivitis
Carbonic anhydrase inhibitor MOA
Inhibit carbonic anhydrase enzymes—> decrease in bicarb ion concentrations—> DECREASE AQUEOUS HUMOR SECRETION —> DECREASE IOP
How do CAIs work systemically?
Increase renal excretion of Na+, K+ HCO3-, H2O—> decreased secretion and production of aqueous humor
What are the oral formulations of CAIs?
Acetazolamide
Methazolamide
What are the topical formulation CAIs available?
Dorzolamide
Brinzolamide
How much IOP lowering do oral agents provide?
25-35%
How much IOP lowering do the topical CAIs provide?
15-20%
Why are oral CAIs typically considered 3rd line?
Due to the intolerable side effects
Indications of use for ORAL CAIs
Short term adjuvant use
Those who do not tolerate or achieve adequate IOP lowering with topicals
Side effects of oral CAIs
Paresthesias (hands and feet)
GI sx (N/V/D)
Metabolic acidosis
electrolyte disturbances (diuresis/ hypokalemia)
Fatigue
Confusion
Drowsiness
Topical CAIs
Dorzolamide & brinzolamide
Have comparable IOP lower
NOT AS EFFECTIVE when compared to other therapies
Not systemic SE
What are the topical CAI side effects?
Hyperemia
Taste Disturbances
Blurred vision
Eye discomfort
What population do we avoid CAI use in?
Patients with Sulfonamide Allergies
(CAIs= sulfonamides)
MOA of cholinergic in POAG
Reduce IOP—> contraction of the ciliary muscle—> high increases aqueous outflow via the trabecular meshwork
Contraction of the iris sphincter muscle—> resulting in pupillary constriction (miosis)
MOA of cholinergic on PACG
Contraction of the iris sphincter pulls the iris away from the trabecular meshwork—> helps unblock the angle
What are the 2 types of Miotics?
Direct-acting Miotics
Indirect Acting Miotics
Direct-acting miotics
Have direct agonistic activity at muscarinic receptors
Indirect-acting miotics
Inhibit acetyelcholinesterase which blocks breakdown of ACh
Miosis limits the amount of light that can pass through the __________
Pupil
Sustained ciliary muscle contraction reduces the ability of the lens to ______________
Occurs at various distances
Cholinergic agents can cause visual impairments especially when?
At night
Dim lighting
Side effects of cholinergic agents
Diarrhea
Stomach cramps
Increased salivation
Eye irritation/ discomfort
Visual impairment at night
Visual impairment to dim light
What are the names of the cholinergic agents used in glaucoma?
Pilocarpine
Echothiopate
How much of an IOP reduction do cholinergic agents provide?
15-20%
MOA of ROCK inhibitors
Increase AH outflow through the trabecular meshwork pathway
What is Netarsudil (ROCK inhibitor) used for?
Additive therapy to PG analogs
Who are ROCK INHIBTORS most effective in treating?
Patients with a lower pre-treatment IOP
18% reduction when initial IOP <27mmHg
Side effects of ROCK inhibitors
Eye redness
Burning
Stinging
When do most clinicians initiate treatment for glaucoma?
2 instances of IOP >25mmHg
Or
2 instances of IOP >22mmHg
Or
Patient with IOP of 18 with cupping and field loss
What is first line therapy for POAG
PG analog
BB
If single medication does not produce an adequate response what should you do?
Switch meds
Increase the dose
Add another agent
What would cause a greater reduction in the IOP than monotherapy?
Combining drops from different classes
A regimen of how many drugs may be needed to produce the desired response in some patients?
2-4
If you dont get a response from the first treatment, what is you next step?
Discontinue
Try medication from a different class
Giving people multiple drug reminds may cause what?
Adherance issues
Risk of multiple drug therapy
Increased side effects
Decreased adherance
CHART:
What do we start therapy with?
BB or PG analog
When do we assess response to BB or PG analogs?
2-4 weeks after start of treatment
What is an alternative first line agent if the patient has contraindications to BB PG analogs?
Brimonidine
If contraindication to β blockers, PG analogs, and brimonidine, what can you give?
Topical CAI
If a patinet has an inadequate response, what steps do you take? (4)
Ensure compliance
Instruct patient on nasolacrimal occlusion (if not already used)
Increase concentration or dose frequency
Switch to alternative 1st line agent if no treatment response, add second first line agent if partial response
What steps do you take if the patient presents with intolerance?
Reduce concentration (if possible)
OR
Change formulations
OR
Switch to class alternative
OR
Switch to alternative first line agent
When taking more than one med, what is recommended to provide optimal ocular absorption and prevent washout?
Wait 5 minutes between drop installations of meds
Doing what during installation helps keep the medications in the eyes and prevents systemic absorption?
Nasal lacrimal occlusion
What color cap are mimotics?
Dark Green
Mydriatic cap color?
Red
