Which symptom is typically associated with hyperthyroidism?

Tachycardia is typically associated with hyperthyroidism because this condition leads to an overproduction of thyroid hormones, which increases the metabolic rate of the body. The excess thyroid hormones stimulate the heart, causing it to beat faster than normal. This acceleration in heart rate is one of the hallmark symptoms of hyperthyroidism, along with other symptoms such as weight loss, increased appetite, anxiety, and heat intolerance.

In contrast, symptoms like weight gain, bradycardia (slow heart rate), and lethargy are more characteristic of hypothyroidism, where there is insufficient thyroid hormone production leading to a decreased metabolic rate. Understanding these associations is crucial for identifying and managing thyroid-related disorders effectively.