DIS - Glaucoma Medications II - Week 5 Flashcards
What is the first choice drug class for treating glaucoma?
Prostaglandins
Are beta blockers advised in low tension glaucoma?
No
What is a good alternative for prostaglandins for glaucoma?
Beta blockers
How many drops per day for prostaglandins, beta blockers, alpha agonists, carbonic anhydrase inhibitors, and muscarinics?
PGA - noce
Beta blocker - bid
Alpha agonist - tid-bid
CAI - gtt tid
Muscarinics - q4h
Is regular use of muscarinics recommended for glaucoma? Explain.
No, do not use for glaucoma
-except as an adjunct for pigment dispersion glaucoma
What is combigan?
Adjunct therapy
-timolol (0.5%) and brimonidine (0.2%) bid
Are adverse effects increased or decreased with combination drug?
Reduced
Do you get the full effect of timolol with combination therapy?
No
What is more typical for children with glaucoma, surgery or eyedrops? Explain.
Surgery - better and more successful outcomes
-temp. drugs before/after surgery
List four issues with eyedrops for children.
Greater absoprtion in children
Dose not tailored for child weight
Immature metabolic pathways
Smaller blood volume gives greater circulating dose/systemic effects
What glaucoma drug class should be avoided in children <2? Explain why.
Avoid alpha agonists - depresses CNS
What is the first choice drug for treating glaucoma in children (which drug specifically, not just drug class)? How should it be administered, considering the issues with eyedrops for children?
PGAs as a first choice - try travatan and continue use if IOP decreases
Minimise drug frequency/dose
Punctal occlusion, eyes closed
When is eye colour change from PGA use most evident?
If only one eye has glaucoma
Can monocular glaucoma be environmental or is it genetic?
Genetic - rare
Can beta blockers be used for combination therapy in children?
Yes, but monitor for bradycardia
True or false
All glaucoma medications cross the placenta
True
What is the safest glaucoma drug for use during pregnancy?
Timolol gel
What is the safest glaucoma treatment option for use during pregnancy?
Selective laser trabeculoplasty
Does IOP naturally increase or decrease during pregnancy? what does this mean for IOP tolerance?
Decreases
-tolerate higher IOP in first trimester
What is the preferred management in pregnant women (4)?
Selective laser trabeculoplasty»_space;> dorzolamide > nyogel > brimonidine
What glaucoma drug class should be avoided in pregnant women?
PGAs
True or false
Not all glaucoma medications secrete into breast milk
False
All of them do
What glaucoma drug class should be avoided in lactating women?
Alpha agonists
-CNS depression
Which of the following are accpetable for lactating women? What is the best time to instil?
PGAs
CAIs
Beta blockers
All of them
Instil immediately after nursing
What is the safest glaucoma treatment option for lactating women?
Selective laser trabeculoplasty
What are the two recommended glaucoma eyedrops for lactating women?
Timolol and dorzolamide
Can brimonidine be used in mothers breastfeeding children <2?
No
What can xalatan induce during pregnancy and should it be used? What about during lactation?
Potential to induce premature labour - avoid use in pregnancy
Use during lactation is ok
What are three kinds of medications that can induce open angle glaucoma? Can these do so through any route of administration? Explain.
Steroids
Traditional medicines
Herbal medicines
All routes of administration cause induce it, but topical is the most potent
What can adrenergic drugs often cause (relating to glaucoma)?
Pupil block
-primary angle closure
What can anticholinergic drugs potentially cause (relating to glaucoma)?
Pupil block
-primary angle closure
What can tri/tetracyclic antidepressant drugs potentially cause (relating to glaucoma)?
Ciliary body effusion
-primary angle closure
What can sulpha based drugs potentially cause (relating to glaucoma)?
Ciliary body effusion
-primary angle closure
Consider angle closure glaucoma. What is the cornea like and what does this mean for drug penetrance? Give an example of a drug with reduced penetration. Keeping this in mind, what is needed?
Swollen cornea with high IOP reduces penetration, especially lipophilic durgs - like PGAs
Need a high dose of drops
Consider angle closure glaucoma. What is the best management (include drop frequency)? Can oral medication be considered? What about IV?
Best - iopidine (0.5%), timolol (0.5%) q2min x4
May need oral drugs - diamox 90 mins after onset
IV drugs to suck fluid from the eye, especially if patient is vomiting
With a pupil block, when does iris ischaemia occur and what does this result in (2)?
Iris ischaemia at high IOP (>40mmHg)
Results in reduced muscle capacity as glucose runs out, then no capacity
What drug can reverse a pupil block, and what is it limited by?
Reversal of pupil block with muscarinic agonist (pilocarpine 2%), limited by iris ischaemia if IOP >40mmHg
Is pilocarpine of any use for a pupil block if IOP is >40mmHg?
No, unless the closure just occurred
What are two hospital means of removing fluid from the eye?
Surgical - paracentesis
Medical - hyperosmotic agents
What are three routes for CAIs depending on urgency?
Intravenous - fast, max effect
Oral - slower, strong effect
Topical - slowest, moderate effect
What are hyperosmotic agents?
Large molecules that stay in the blood but are also non-toxic to the body
Give two examples of oral hyperosmotic agents. Include dosage per kg weight, onset, and duration.
Glycerine
-1 to 1.5g/kg
-onset 30-60m
-duration ~6h
Isosorbide
-1 to 3g/kg
-onset 30m
-duration dw
Give two examples of intravenous hyperosmotic agents. Include dosage per kg weight, onset, and duration.
Mannitol
-1 to 2g/kg
-onset 5m
-duration ~4h
Urea
-1 to 2g/kg
-onset 5m
-duration ~5h
List a contraindication for mannitol. In what two conditions should it be used with caution?
Excessive diureses
Caution with renal diease and congestive heart failure
How long does IV diamox take to reduce aqueous production if given IV?
10-20 mins for 2h
List three side effects of diamox.
GI irritation
Numbness of periorbital region and extremities
List 6 contraindications for CAIs.
Renal disease
Liver disease
COPD
Sulphur allergy
Pregnancy
Metabolic acidosis
What time period of ischaemia to the optic nerve head will lead to total loss of vision?
48 hours
What is the definitive intervention for acute angle closure glaucoma?
Surgery in both eyes
PLI/iridoplasty/trabeculectomy
List the OBA recommendation of first aid for acute angle closure glaucoma, including how long between drops (6). Give an example of the drug where applicable, including concentration.
1 drop beta blocker (timolol 0.5%)
1 drop alpha agonist (alphagan 0.2%)
1 drop CAI (trustopt 2%)
1 drop pilocarpine (2%)
1 drop pred forte if eye is inflammed
-2 minutes between drops
Urgent referral
Consider a case of acute angle closure glaucoma in the absence of a hospital within an hour. What should be done in this case (2)?
Oral diamox 2x250mg
500mg K+
-go to the pharmacy if necessary
When should pilocarpine not be used in first aid for acute angle closure glaucoma?
Shallow Ac - retrolental cause
Does IOP splike on dilation even with open angles?
Yes, 7% of patients show a spike
Consider a pupil block induced by mydriasis. What will typically reverse it (2)?
Topical pilocarpine followed by alpha agonist 2 mins apart for most people
What are two indications of iris ischaemia?
Cloudy cornea
Pupil unresponsive
What should be done with patients who spike with mydriasis?
Pretreat with alphagan before dilating (if IOP >30mmHg during spike)
Name a laser procedure to reduce aqueous inflow to decrease IOP.
Laser or cryodestruction of ciliary body
Name two laser procedures to increase aqueous outflow to decrease IOP. Explain each and note which is not used nowadays.
Argon laser trabeculoplasty - punch holes in the TM
-tightens the meshwork on scar formation, not used nowadays for glaucoma
Selective laser trabeculoplasty - stimulates trabecular cells with low dose laser
-acts by increasing phagocytic activity and inflammatory response
Name two surgical procedures to increase aqueous outflow to decrease IOP.
Trabeculoplasty - cut and remove TM or reshape it with laser
Trabeculectomy - create a new drainage channel to drain to the sub-conjunctival flap
What is a minimally invasive glaucoma surgery?
Implant that facilitates aqeuous drainage
Consider laser surgery options for glaucoma. How does pigment affect it and what does this mean for dark-skinned people?
Both procedures are related to the amount of pigment
-dark-skinned people have better outcomes
Compare laser treatment to topical drugs in terms of glaucoma target IOP outcomes. what does Australia recommend as the first line therapy and what is the main issue? Compare costs.
Laser treatment tends to offer better outcome son reaching target IOP vs drops
-compliance is the main issue
Australia still recommends topical drops as first-line
Cheaper with laser treatment if only one procedure performed vs drops
-26% need two proceudres
Does minimally invasive glaucoma surgery have a high or low safety profile? Compare complications and recovery rate to trabeculectomy.
High safety profile
Fewer complications and more rapid recovery time than trabeculectomy
What is used to limit scarring and prevent surgically created alternate routes from sealing over in trabeculectomy? What is a complication of this?
Antimetabolites
-can cause tissue to melt
List three complications of trabeculectomy.
Poor IOP control
Infection
-blebitis
-endophthalmitis
What surgical procedure is the last resort for neovascular glaucoma?
Laser/cryo-ablation of ciliary body
