Antiarrhythmic drugs are associated with significant side effect profiles. Amiodarone has primarily class III action and whilst it has unrivalled efficacy in management of certain arrhythmias, it has a formidable side effect profile. Complications of continued therapy include, thyroiditis, hepatitis, cholestasis, increased skin sensitivity and pulmonary fibrosis. Current prescribing guidelines recommend frequent blood tests to monitor kidney, liver and thyroid function, in addition to frequent pulmonary function tests. Sotalol is a betablocker which possesses class III action in high doses and may predispose to QT prolongation Other class I agents such as flecainide and propafenone can be associated with sudden cardiac death in certain populations, and may predispose to other arrhythmias.

This study will examine the incidence of discontinuation of AAD therapy and adverse events.

Inclusion Criteria:

• At least one prescription for antiarrythmic drug

All patients in Tayside receiving a prescription for an anti-arrythmic drug since 1994