Anti-arrhythmics Flashcards
What type of drug are class 1 anti-arrhythmics?
Sodium channel blockers
Give an example of a class 1 anti-arrhythmic
Flecainide
Lidocaine
What is the action of Class 1 anti-arrhythmics? (3)
Bind and block sodium channels
Reduces phase 0 (depolarisation)
Decrease AP amplitude
Name another condition that sodium channel blockers can be used for
Epilepsy
What type of drug is a class 2 anti-arrhythmics?
Beta blockers
What is the action of class 2 anti-arrhythmics? (4)
Blocks sympathetic activity
Reduces rate and conduction of AP
Slows down phase 4 (prolongs time between AP)
Lowers HR
Give an example of a beta blocker
Atenolol
Bisoprolol
What can beta blockers also be used for?
Hypertension
Heart failure
How would you treat a beta blocker overdose?
Give atropine
Glucagon is atropine is not successful
What are class 3 anti-arrhythmics?
Potassium channel blockers
Give an example of a class 3 anti-arrhythmics
Amiodarone
Sotalol
What is the action of class 3 anti-arrhythmics? (5)
Delays repolarisation Increases duration of AP Prolongs phase 3 Prolongs refractory period Decreases HR
What type of drug are class 4 anti-arrhythmics?
Calcium channel blockers
What is the action of class 4 anti-arrhythmics?
Blocks L-type Ca2+ channels
Slows conduction through AVN
Prolongs phase 2
Decreases HR
What are calcium channel blockers used for a lot? Why?
SVT
They block re-entry mechanism by slowing down conduction through AVN