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Discussion Starter #1
A 54-year-old male is hospitalized with atrial fibrillation and rapid ventricular response. He had a similar episode three months ago. After treatment, his arrhythmia is corrected and he becomes asymptomatic. You consider long-term amiodarone therapy to prevent future arrhythmic episodes. Which of the following should be tested before initiation of the therapy?


A. Serum prolactin
B. Serum TSH
C. 24-hour urinary cortisol excretion
D. 24-hour urinary VIVA excretion
E. Oral glucose tolerance test
F. Serum calcitonin

plz try your best, don't be hesitated.
 

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B. Serum TSH

Amiodarone is a Iodine analogue and hence thyroid function will be affected by it. The famous side effect of this drug is pulmonary fibrosis.

Hope this is right.
 

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Amiodarone is a class III anti-arrhythmic agent used to suppress life-threatening cardiac conduction abnormalities. It has multiple side-effects, and most patients on chronic amiodarone therapy can expect at least one of the following: thyroid dysfunction corneal micro-deposits, blue-gray skin discoloration, drug-related hepatitis, or pulmonary fibrosis (rare, but life-threatening).

Amiodarone causes thyroid dysfunction because it is 40% iodine by weight. Amiodarone induced hypothyroidism is due to excessive iodine and occurs in 5-20% of the amiodarone-treated patients in iodine- sufficient regions. Patients with preexisting autoimmune thyroid disease are at a greater risk for hypothyroidism, which is why thyroid functions are routinely measured before and during treatment with amiodarone. Amiodarone induced hypothyroidism is treated with levothyroxine and amiodarone is typically continued.

Amiodarone can also induce thyrotoxicosis due to excessive production of thyroid hormone and primarily seen with patients living in iodine-deficient areas.
 

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Yup- the mnemonic for amiodarone toxicity is "Remember to check PFTs TFTs and LFTs as Amiodarone can cause thyrotoxicity, hepatotoxicity and pulmonary fibrosis.
 
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