Which finding is consistent with thyrotoxicosis?

• A. Bradycardia
• B. Menorrhagia
• C. Nervousness
• D. Constipation

Answer: (C)

Thyrotoxicosis increases metabolic rate and heightens sympathetic nervous system activity, leading to symptoms such as anxiety, irritability, tremor, palpitations, and heat intolerance. Nervousness is a classic manifestation because exactly this heightened adrenergic responsiveness drives anxious, jumpy feelings.

Bradycardia would not fit, since thyrotoxicosis typically causes tachycardia rather than a slow heart rate. Constipation goes against the hypermotility of the GI tract seen in thyrotoxicosis, which more often produces diarrhea. Menstrual changes can occur with thyroid disorders, but heavy menses aren’t a hallmark feature of thyrotoxicosis.