Which of the following is a symptom of hyperthyroidism?

Hyperthyroidism is characterized by an overactive thyroid gland that produces excessive amounts of thyroid hormones, leading to a range of symptoms due to increased metabolic activity. One prominent symptom is anxiety, which occurs as a result of heightened levels of thyroid hormones stimulating the central nervous system. This stimulation can cause feelings of nervousness, restlessness, and heightened emotional responses, all of which are common in individuals with hyperthyroidism.

In contrast, symptoms such as weight gain, bradycardia (slow heart rate), and cognitive impairment are typically associated with conditions like hypothyroidism, where there is an underproduction of thyroid hormones. These symptoms differ fundamentally from the signs of hyperthyroidism, highlighting the importance of understanding how thyroid hormone levels influence body functions. The presence of anxiety serves as an important indicator for clinicians when assessing thyroid function and diagnosing hyperthyroid conditions.