[Amiodarone and the thyroid].
Amiodarone is an iodine-rich drug widely used for the management of cardiac arrhythmias. During long-term amiodarone therapy drug toxicity may occur and a substantial proportion of amiodarone-treated patients develop either hypothyroidism or thyrotoxicosis. Several mechanisms are involved in amiodarone-induced thyroid dysfunction: defective thyroid auto-regulatory mechanism in presence of excessive iodine offer, immunological factors and cytotoxicity. Approximately 50% of patients taking amiodarone present abnormal thyroid function. Therefore, for adequate clinical follow up of these patients, it is critical a careful monitoring of thyroid hormones and TSH, before and during treatment.
Pavan
Renata
R
Divisão de Endocrinologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP.
Jesus
Alexandre M X de
AM
Maciel
Léa M Z
LM
D000638:Amiodarone / Q000009:adverse effects*; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects*; D006801:Humans; D013971:Thyrotoxicosis / Q000139:chemically induced*
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone