| Drug Class |
Cardiac glycoside |
| Mechanism |
- Inhibits Na/K pump - ↑ intracellular Na conc inhibiting Na/Ca pump
- ↓ Ca pumped out of cell - ↑ force of contraction
- ↑ vagal activity, ↓ HR/AV node conduction
|
| Typical Dose |
125-250 micrograms |
| Indications |
- HF
- Supraventricular arrhythmias (esp fast AF aim for HR <100)
|
| Contra-indications |
- Complete heart block
- HOCM
- WPW syndrome
|
| Side-effects |
Common: nausea, vomiting, anorexia, visual disturbances
Rarely: confusion, hallucinations
|
| Interactions |
- Amiodarone/propafenone/quinidine: antiarrhythmics ↑ risk of digoxin toxicity
- CCBs: ↑ risk of digoxin toxicity
- Diuretics: hypokalaemia can ↑ risk of toxicity
|
| Elimination |
Excreted via the kidneys |
| Additional Notes |
- Can cause ST depression - digoxin effect
- Weak +ve inotrope, half life of 36 hours
|
ALPHA