Which of the following is a sign of thyrotoxic crisis in Graves' disease?

• A. Pallor
• B. Bradycardia
• C. Fever
• D. Weight gain

Answer: (C)

Thyrotoxic crisis, or thyroid storm, is an extreme, life-threatening flare of Graves’ hyperthyroidism that launches the body into a high‑metabolic state. Fever is a hallmark of this crisis because the excessive thyroid hormones drive intense heat production and overwhelm the body’s ability to dissipate heat. This hypermetabolic drive is paired with sympathetic overactivity, leading to rapid heart rate, sweating, and agitation, all of which commonly accompany the fever.

Pallor is not typical in this setting; bradycardia would oppose the usual fast heart rate seen in a thyroid storm, and weight gain would be contrary to the weight loss that often accompanies hypermetabolism. So fever stands out as a key sign of thyrotoxic crisis in Graves’ disease.