Amiodarone is an antiarrhythmic drug belonging to Vaughan-Williams Class III with additional Class IV effects, which is known to cause many adverse drug reactions (ADRs) necessitating close monitoring. In about 20% of patients, their therapy is discontinued due to adverse effects such as hepatic impairment, thyroid dysfunction, and several pulmonary complications. Although dyselectrolytemia is a common adverse reaction reported with many cardiac medications, the incidence of hyponatremia associated with amiodarone intake is not reported widely in the literature. We are reporting a case of a 73-year-old female patient, with hypertension and ischemic heart disease (IHD) receiving oral amiodarone, presenting with severe hyponatremia, requiring recurrent hospitalization. Amiodarone was found to be responsible after evaluating for the possible causes of hyponatremia. As the incidence of amiodarone-associated hyponatremia is unknown, and not many cases are reported, this case report serves to sensitize the clinician to consider amiodarone-induced hyponatremia as one of the differential diagnoses in cases of unexplained hyponatremia.
Keywords: adverse drug reaction; amiodarone; hyponatremia; syndrome of inappropriate antidiuretic hormone secretion.