Monitoring side effects of amiodarone in general practice

The potential complications from amiodarone are legion and therefore monitoring is important

Before treatment with amiodarone:

• patients should have careful clinical assessment, measurements of liver enzymes, thyroid function tests and serum potassium, an ECG and chest X-ray

After treatment with amiodarone has commenced:

• it is advised that all patients taking amiodarone should have their liver function tests and thyroid function tests checked every six months (1,2). Also they should possibly have potassium levels monitored 6 monthly (2).
• a Drug and Therapeutics Bulletin review suggests that eye examinations should be reserved for patients reporting visual symptoms (2) - this contrasts with other advice (1) which suggests that patients should have their eyes checked annually by slit examination.
• at the first hint of worsening of breathlessness or cough organise lung function tests as amiodarone can cause fibrosing alveolitis. Symptoms suggestive of pulmonary toxicity or hyperthyroidism require urgent referral (2)
• patients should be advised to limit sunlight exposure and to use a sunscreen.

Reference:

1. MeReC Bulletin (2002), 12 (5), 17-20.
2. Drug and Therapeutics Bulletin (2003), 41 (2), 9-12.