Digoxin & Digoxin Toxicity

Question 1

What type of drug is digoxin?

Answer 1

A cardiac glycoside

Question 2

In what 2 conditions can digoxin be used?

Answer 2

1. AF - rate control
2. Heart Failure - it improves symptoms but not mortality outcomes.

Question 3

What is the mechanism of action of digoxin?

Answer 3

1. It decreases conduction through the AV node which slows the ventricular rate in AF and flutter.
2. It increases the force of cardiac muscle contraction by inhibiting the Sodium/Potassium/ATPase pump.
3. It can also stimulate the vagus nerve.

Question 4

What are some symptoms/signs of digoxin toxicity?

Answer 4

• Arrythmias (AV block, bradycardia)
• Generally unwell-
  
  • Lethargy
  • N&V
  • Anorexia
  • Confusion
  • Yellow-Green vision.

Question 5

How should one manage digoxin toxicity?

Answer 5

1. Digibind
2. Correct arrhythmias
3. Monitor potassium

Question 6

What is the classic condition that causes digoxin toxicity?

Answer 6

Hypokalaemia

Question 7

What conditions can precipitate digoxin toxicity?

Answer 7

1. Hypokalaemia is the classic one.
2. Increasing age
3. Renal failure
4. Myocardial ischaemia
5. Electrolyte abnormalities: Hypomagnesaemia, hypercalcaemia, hypernatraemia.
6. Hypoalbuminaemia
7. Hypothermia
8. Hypothyroidism

Question 8

What drugs can cause digoxin toxicity?

Answer 8

• Amiodarone
• Quinidine
• Verapamil
• Diltiazem
• Spironolactone
• Ciclosporin
• And drugs that cause hypokalaemia (furosemide and thiazide diuretics)

Question 9

What can digoxin do to your vision?

Answer 9

Turn it yellow.

Question 10

Can digoxin toxicity occur with normal levels?

Answer 10

Yes