All of the following are true about amiadarone induced thyroid dysfunction except?
**Core Concept**
Amiodarone-induced thyroid dysfunction is a well-documented side effect of this antiarrhythmic medication. It can cause both hypothyroidism and hyperthyroidism due to its high iodine content and its impact on thyroid hormone synthesis and release.
**Why the Correct Answer is Right**
Amiodarone contains approximately 37% iodine by weight, which can cause thyroid dysfunction in susceptible individuals. The high iodine content can lead to increased thyroid hormone synthesis, resulting in hyperthyroidism, or it can cause thyroid inflammation (thyroiditis) and subsequent hypothyroidism. Additionally, amiodarone can cause destructive thyroiditis, leading to transient hyperthyroidism followed by hypothyroidism.
**Why Each Wrong Option is Incorrect**
**Option A:** Hypothyroidism is indeed a known side effect of amiodarone, making this option incorrect.
**Option B:** Amiodarone-induced thyroid dysfunction can cause both hyperthyroidism and hypothyroidism, making this option incorrect.
**Option C:** Amiodarone's high iodine content is the primary cause of thyroid dysfunction, making this option incorrect.
**Clinical Pearl / High-Yield Fact**
Amiodarone-induced thyroid dysfunction can be challenging to manage, and patients often require close monitoring of thyroid function tests and thyroid-stimulating hormone (TSH) levels. A high index of suspicion is necessary to diagnose and treat this condition promptly.
**Correct Answer:**
Correct Answer: **A**.