Choice of anti-arrhythmic agent depends on the type of arrhythmia - see BNF and NICE guidance. These would mainly be initiated in secondary care.
Drug safety Update
March 2022: Amiodarone (Cordarone X): reminder of risks of treatment and need for patient monitoring and supervision
October 2011: Dronedarone (Multaq▼): cardiovascular, hepatic and pulmonary adverse events – new restrictions and monitoring requirements
Drug level monitoring of digoxin is recommended because it has a narrow therapeutic index and therefore should be used with caution in the elderly and in renal impairment. Therapeutic concentrations of digoxin are quoted as 0.8 - 2.2 micrograms/L, but results should be interpreted alongside clinical findings and serum potassium levels. Measurement of digoxin levels should be taken at least 6 hours post dose. See local Therapeutic Drug Monitoring Guidance.
Patients are at an increased risk of digoxin toxicity if hypokalaemia occurs.
Administration route: when changing from tablets to elixir, ONE 62.5micrograms tablet is approximately equivalent to 50micrograms(1mL) elixir.
Amiodarone requires careful monitoring. See BNF for cautions, side effects, interactions and monitoring.
Dronedarone is a derivative of amiodarone. It must be used second line to other anti-arrhythmic agents including amiodarone. See BNF for cautions, side effects, interactions and monitoring. There is a shared care guideline for prescribing.