Drug Class: IIC Anti-arrhythmics - K+ Channl Blockers

Question 1

Examples of IIC anti-arrhythmics

Answer 1

AMIODARONE
BRETYLIUM
SOTALOL

Question 2

Mode of action of IIC anti-arrhythmics

Answer 2

Delayed repolarisation by K+ channel blockade

• Increase AP duration
• Stops exit of K+ from cell= prolongs phase 3 repolarisation
• Prolongs Effective refractory period

Question 3

Side effects of IIC anti-arrhythmics

Answer 3

Arrhythmias

Pro-arrhythmias

Question 4

Side effects of AMIODARONE

Answer 4

High iodine

• Hypo or hyperthyroidism
• Pulmonary/ liver fibrosis
• Slate grey pigmentation
• Corneal deposits
• Liver Function Tests abnormalities

Question 5

Drug-drug interactions of AMIODARONE

Answer 5

• Digoxin-> competition for albumin binding = ↓ digoxin dose before starting

Question 6

What are III C Anti-arrhythmics used for

Answer 6

• V tach
• V fib
• A fib
• Atrial flutter