Antidysrhythmics Flashcards
1
Q
What are class I cardiac antidysrhythmic drugs?
A
They are membrane stabilizers that work by inhibiting fast sodium channels.
2
Q
How do class II antidysrhythmic drugs work?
A
They are beta-adrenergic antagonists that depress automaticity by decreasing spontaneous phase 4 depolarization in nodal tissues and decrease conduction speed of cardiac impulses.
3
Q
How do class III antidysrhythmic drugs work?
A
They prolong repolarization by blocking voltage-gated potassium channels, effectively prolonging the effective refractory period in the SA and AV nodes, atria, ventricles, and His-Purkinje fibers.
