Much less commonly, elevated thyroxine levels can be drug-induced (amiodarone, interferon alpha)
5% after a single dose of more than 10 Amiodarone and the Thyroid, Seminara and Daniels 49 Fig
Levels below this range are more likely to be associated with ineffectiveness, and levels above this range are likely to be associated with toxicity and increased side effects
These values do not apply to results that are converted to other units of measure
Desethylamiodarone
The high prevalence of adverse effects has resulted in decreased use of the drug 2
After amiodarone treatment he presented a clinical and analytical picture of hyperthyroidism with very low TSH levels and increased free-T4 levels
General considerations
AIH is treated by L-thyroxin replacement and does not need amiodarone discontinuation
Though classified as a class III antiarrhythmic, it affects all phases of the cardiac action potential
Am J Med Hypothyroid side effect: in normal patients, high levels of iodine associated with amiodarone therapy typically contribute to a transient inhibition of thyroid hormone synthesis due to an auto-regulatory mechanism within the thyroid (the Wolff-Chaikoff effect)
Amiodarone is commonly utilized for treating both supraventricular and ventricular arrhythmias
In addition, amiodarone decreases the clearance of both T 4 and of reverse T 3, and Amiodarone is recognized to act at different enzymatic and non-enzymatic levels in the thyroid: It inhibits type 1 5′-deiodinase enzyme activity thereby it decreases the peripheral conversion of thyroxine (T 4 ) to triiodothyronine (T 3 ) and reduces the clearance of both T 4 and reverse-T 3