Digoxin

Question 1

in what patients is digoxin prioritised?

Answer 1

sedentary with permanent AF

Question 2

how does digoxin work for AF?

Answer 2

slows conductivity and ventricular response at AV node
negative chronotrope- dcerease HR

Question 3

how does digoxin work for heart failure?

Answer 3

increases force of myocardial ventricular contraction (positive inotrope)
vagal nerve stimulation

Question 4

dose range for heart failure?

Answer 4

62.5 -125mcg OD

Question 5

maintenance dose range for AF?

Answer 5

125-250mcg daily

Question 6

when to monitor for therapeutic levels?

Answer 6

take bloods 6hrs post dose

Question 7

what is the therapeutic level of digoxin?

Answer 7

1-2mcg/L

Question 8

what plasma concentration will see no therapeutic effect?

Answer 8

<0.5 mcg/L

Question 9

At what level is there increased risk of toxicity?

Answer 9

2-2.5 mcg/L

Question 10

how to spot signs of toxicity?

Answer 10

SLOW and SICK
bradycardia
confusion
blurred/yellow vision
Nausea, vomiting, diarrhoea
rash

Question 11

steps to take to treat toxicity?

Answer 11

stop digoxin
correct electrolyte imbalance
digoxin specific antibody FAB fragment (DIGIFab)

Question 12

Drug types that interact with digoxin?

Answer 12

1 - medicines causing HYPOkalaemia
2 - medicines that increase plasma con. (enzyme inhibitors)
3 - medicines that decrease plasma conc. (enzyme inducers)
4- medicines that decrease excretion

Question 13

acronym to remember some drug interactions?

Answer 13

CRASED
CCB - hypokalaemia
Rifampicin - enzyme inducer
Amiodarone - enzyme inhibitor
St john wort - enzyme inducer
Erythromycin - enzyme inducer
Diuretics - hypokalaemia