Potassium channel blockers

Definition

Potassium channel blockers are a class of antidysrhythmic drugs that inhibit the flow of potassium ions through cardiac cell membranes, prolonging repolarization and action potential duration. They are primarily used to treat various types of cardiac arrhythmias.

5 Must Know Facts For Your Next Test

1. Potassium channel blockers prolong the repolarization phase (phase 3) of the cardiac action potential.
2. They are classified as Class III antidysrhythmic drugs according to the Vaughan-Williams classification system.
3. Amiodarone and sotalol are commonly prescribed potassium channel blockers.
4. These drugs can increase the risk of torsades de pointes, a potentially life-threatening type of ventricular tachycardia.
5. Potassium channel blockers can interact with other medications, necessitating careful monitoring for adverse effects.

Review Questions

• What is the primary mechanism of action for potassium channel blockers?
• Name two commonly prescribed potassium channel blockers.
• What is a major risk associated with the use of potassium channel blockers?

Related terms

Antidysrhythmic Drugs:

Medications used to treat abnormal heart rhythms.

Vaughan-Williams Classification System: A system used to categorize antidysrhythmic drugs into four main classes based on their mechanism of action.

Torsades de Pointes:

A specific type of ventricular tachycardia characterized by a rapid, irregular heartbeat that can lead to sudden cardiac death.