Anti-Arrhythmic Drugs Flashcards
Class 1a & 1c
Main Target
Na+ channel blockers
Class 1a & 1c
Main action
↓conduction rate,
↑refractory period
Class 1a & 1c
side effects
Can block fast and slow response cells, K+ chan
Class 1a & 1c
examples
a: quinidine, procainamine
c: flecainide
Class 1b
Main Target
Na+ channel
blockers
Class 1b
Main action
↓conduction rate
↑refractory period
Class 1b
side effects
Can block Ca2+ channels (Class 4 action)
Class 1b
examples
Lidocaine
Class 2: Beta blockers
Main Target
B-adrenergic receptor blockers
Class 2: Beta blockers
Main action
Reduces pacing rate and prolongs
refractory period in SA/AV node
Class 2: Beta blockers
side effects
Block Ca2+
-L, K+, If
Class 2: Beta blockers
examples
Propranolol
Metoprolol
Class 3
Main Target
K+ channel
blockers
Class 3
Main action
Prolong phase 2, and thus refractory period by
↑ Na+ inactivation
Class 3
side effects
Na+ blocking (amiodarone),
qB-blocking (sotalol)
Class 3
examples
Amiodarone
Ibutilide
Class 4
Main Target
L-type Ca2+ channel blockers
Class 4
Main action
Slows upstroke and depolarization
in nodal cells, and repolarization
Class 4
side effects
Can block fast response as well. Slower
upstroke causes fewer K+ to open
Class 4
examples
Verapamil
Diltiazem
Adenosine
Main Target
A1 adenosine
receptor
Adenosine
Main action
↑K+ current, ↓L-type Ca2+ and If
in SA and AV nodes
Adenosine
side effects
Intended: causes heart to slow down for a
minute- good emergent
Adenosine
examples
Unclassified:
Adenosine,
Digoxin
Isoproterenol
