Mx Exam Revision Flashcards
What is the 1st-choice pharmaceutical treatment for reducing IOP in glaucoma and why?
Prostaglandin Analogues [specifically Xalatan]: highest efficacy [30% reduction] and once-daily usage [24hr IOP control] is convenient.
List 4 potential side effects of prostaglandin analogues
Darker iris
Lash growth
Loss of orbital fat
Red eye [either short term or long term]
List 4 different options for prostaglandin analogues, including their dosage percentages
Latanaprost [Xalatan 0.005% NOCTE]
Travaprost [Travatan 0.004% NOCTE]
Bimatoprost [Lumigan 0.03% NOCTE]
Tafluprost [Zioptan 0.0015% NOCTE]
** that’s right lumigan is actually 0.03%
What alternative prostaglandin can you consider if Xalatan is only achieving a small reduction (IOP redcution <5mmHg)? Why?
You could try Lumigan or Travatan.
Lumigan has a different chemical composition and some studies suggest it can have a greater IOP lowering effect. There’s a preservative free lumigan you can use.
Travatan can also be considered as it binds better to PGF2alpha, however the chemical composition is similar to Xalatan so it might not have much greater an effect. Travatan does use polyquad preservative rather than BAK like xalatan, so that’s another benefit.
What downside may occur in switching from xalatan to travatan?
May have more adverse/side effects
Of the 4 mentioned prostaglandin options, which results in the least side effects and least conjunctival hyperaemia?
Xalatan.
List 3 contraindications for prostaglandin analogues
Uveitis
Pregnancy
HSV
List 3 prostaglandin analogues to consider for a patient with ocular surface disease or sensitivity to BAK preservative
Travaprost [uses an ionic buffered preservative - polyquad]
Tafluprost [preservative free]
Preservative-free Lumigan [specifically the preservative free kind]
Aside from PGAs, list 3 other drug classes that can be used to reduce IOP in open angle glaucoma
Carbonic Anhydrase Inhibitors
Beta Blockers
Alpha Agonists
Which drug class makes the best adjunct to PGAs?
CAIs. Because PGAs secondary action promotes the action of CAIs.
What is the ideal patient for PGAs?
Those with a chronic, non-acute IOP elevation (i.e. POAG and NOT aacg or post-op iop spike)
List 2 topical CAI options for reducing IOP
Dorzolamide [Trusopt 2% TiD]
Brinzolamide [Azopt 1% BiD]
List 4 benefits for topical CAIs
Reduces diurnal fluctuation
Good vascular nocturnal profile
Fast effect [1 hr]
Good adjunct to PGAs
Which topical CAI has less stinging? Dorzolamide or Brinzolamide? Why?
Brinzolamide. It coms in a 10mg/ml suspension which means it has a slower release and therefore less stinging.
List 1 contraindication for CAIs
Corneal graft/corneal compromise. Topical CAIs can result in corneal deturgescence.
Which glaucoma drops are safest to use in the first trimester?
Brimonidine [an alpha agonist] may be the safest option for the first trimester. [** it’s also generally the safest drug as it’s a category B1 drop]
Which glaucoma drops are safest to use in the second trimester? (3)
Brimonidine
Beta blockers [with regular fetal heart rate/growth monitoring]
CAIs [with fetal growth monitoring]
Which glaucoma drops are safest to use in the third trimester? (3)
Brimonidine [must discontinue late in 3rd trimester to avoid CNS depression in newborns]
Beta blockers
Topical CAIs
**All to be used with caution
What are the main risks associated with glaucoma surgery in pregnant patients? (4)
the usage of local anaesthetics
post-operative meds
gastro-oeseophageal reflux
increased risk of aortic + vena cava compression in 2nd/3rd trimester
Name an alternative to traditional glaucoma surgery that can be safer for pregnant patients. Why? (4)
Selective Laser Trabeculectomy (SLT):
- only uses topical anaesthesia
- upright positioning during procedure
- faster rehab
- reduced need for post-op meds [both dosage + duration]
When is the ideal time to consider surgery for a pregnant patient?
Before their (planned) pregnancy, as a way to manage IOP without having them on drops
Does IOP naturally rise or lower during pregnancy? By how much? Why? When is this most pronounced?
IOP diminishes by up to 10% during pregnancy, most pronounced in the 3rd trimester. Is attributed to fluctuating hormones [β-human chorionic gonadotropi and progesterone]
Is MIGS-iStent safe for pregnant patients?
Yeah-ish. About as safe as SLT anyway.
List the IOP reduction efficacies, in percentage, for the 4 different drug classes used in primary open angle glaucoma
PGAs: 30%
Beta Blockers: 25-30%
Topical CAIs: 20%
Alpha agonists: ~25% ish. Unsure. Expect maybe a 5-6mmhg reduction.
[update on the role of alpha agonists in glaucoma management]