UMEM Educational Pearls

Category: Airway Management

Title: Amiodarone and Thyroid Disease

Keywords: thyroid, hyperthyroid, hypothyroid, amiodarone (PubMed Search)

Posted: 7/5/2011 by Haney Mallemat, MD
Click here to contact Haney Mallemat, MD

Amiodarone is a class III anti-arrhythmic for tachyarrhythmias

Although most patients remain euthyroid on amiodarone, 4-18% develop thyroid disease months to years after exposure.

Amiodarone-induced thyroid disease occurs because amiodarone is structurally similar to triiodothyronine and thyroxine and each 200mg tablet contains 75 mg of iodine.

Two types of amiodarone-induced thyroid disease:

  • Amiodarone-induced hypothyroidism (AIH)
  • Amiodarone-induced thyrotoxicosis (AIT)

Amiodarone-induced hypothyroidism (AIH)

  • Presents with subtle to overt hypothyroidism 
  • Treat by discontinuing amiodarone; thyroid recovers within 3 months
  • If amiodarone cannot be discontinued, start levothyroxine

Amiodarone-induced thyrotoxicosis (AIT)

  • Sudden symptom onset months to years following exposure; mean 2-47 months post-exposure
  • Can be a life-threatening presentation (similar to thyroid storm) with severe cardiac manifestations and hemodynamic instability
  • Treatment (treat like thyroid storm, if severe)
    • Discontinue drug, if possible
    • Thionamides (inhibit enzyme producing thyroid hormones)
    • Methimazole or propylthiouracil
    • Beta-blockers
    • Steroids
    • Airway and hemodynamic support


Padmanabhan H. Amiodarone and Thyroid Dysfunction. South Med J. 2010 Sep; 103 (9): 922-30

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