Digoxin

Question 1

What class of drug is digoxin?

Answer 1

Cardiac Glycoside

Question 2

What is digoxin used for?

Answer 2

Rate Control in AF (slows heart rate and increases contraction force)

Question 3

What is the dose for rapid digitalisation (loading dose)?

Answer 3

0.75mg - 1.5mg over 24 hrs (or over 2 hrs in an emergency)

–> reduce dose in elderly

Question 4

What is the maintenance dose for AF?

Answer 4

125 - 250 mcg daily

Question 5

What is the maintenance dose for Heart Failure (in sinus rhythm)?

Answer 5

62.5 - 125 mcg daily

Question 6

Therapeutic Range of Digoxin

Answer 6

0.7 - 2 ng/ml

Question 7

When should digoxin levels be taken?

Answer 7

6 - 12 hours AFTER a dose

Question 8

What level is associated with digoxin toxicity?

Answer 8

1.5 - 3 ng/ml

Question 9

Symptoms of Digoxin Toxicity

Answer 9

SICK and SLOW
Bradycardia
Diarrhoea and Vomitting
Dizziness
Confusion
Depression
Yellowed or Blurred Vision

Question 10

Common Interactions with Digoxin

Answer 10

Beta Blockers
TCAs (can induce arrhythmias)
Drugs causing hypokalaemia (diuretics)
Drugs impairing renal function
CYP inducers and inhibitors

Question 11

What 3 drugs do you need to use half-dose digoxin with?

Answer 11

Amiodarone
Quinine
Dronedarone

Question 12

If switching from IV to oral - what do you do with the dose?

Answer 12

Increase by 20 - 33%

Question 13

If another cardiac glycoside has been given in the last 2 weeks, what do you do with the new dose of digoxin?

Answer 13

Reduce it

Question 14

Cautions with Digoxin

Answer 14

Elderly (> 125mcg long term with eGFR < 30)
Hypokalaemia
Hypomagnesemia
Hypercalcaemia
Hypoxia

Question 15

Monitoring Requirements for Digoxin

Answer 15

Renal function
Electrolytes
Heart Rate (> 60 bpm)
Plasma digoxin

Question 16

What is the main electrolyte imbalance tat can increase risk of digoxin toxicity?

Answer 16

Hypokalaemia