[Effects of amiodarone on thyroid function].
Amiodarone has been used in cardiology for more than 20 years as an anti-angina and anti-arrhythmia agent. In the seventies, variations in thyroid hormone and TSH concentrations were described in treated patients. Only recently, however the pathogenic mechanisms leading to dysthyroidism in long-term treatment have been described. Today, the gravity of amiodarone-induced hyperthyroidism has been greatly reduced due to a better understanding of the underlying mechanisms and better surveillance of thyroid function. In clinical practice, the following attitude can be proposed. Thyroid exploration should be completed before prescribing amiodarone: clinical examination should emphasize personal or familial history in search of dysthyroidism or goitre; hormone assays (TSH, free T4) are needed to eliminate any latent thyroid dysfunction, particularly hyperthyroidism with little or no clinical manifestation but sometimes the causal factor in cardiac symptomatology; search for a significant level of anti-thyroperoxidase antibodies can reveal underlying chronic thyroiditis. After prescription, clinical surveillance and TSH assay should be performed at 3 months then every 6 months during treatment. After withdrawal, surveillance should be continued with check-ups at 6 and 12 months.
Caron
P
P
Service d'Endocrinologie, CHU Rangueil, Toulouse.
D000638:Amiodarone / Q000009:adverse effects*; D000787:Angina Pectoris / Q000188:drug therapy; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects*; D006801:Humans; D006980:Hyperthyroidism / Q000139:chemically induced*; D007037:Hypothyroidism / Q000139:chemically induced*
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone
Effets de l'amiodarone sur la fonction thyroïdienne.