American Board of Internal Medicine (ABIM) Certification Practice Exam

What is one of the preferred agents for the treatment of thyroid storm?

1. Levothyroxine

2. Propranolol

3. Metformin

4. Insulin

The correct answer is: Propranolol

Propranolol is recognized as a preferred agent for the treatment of thyroid storm due to its ability to rapidly reduce the symptoms associated with this critical condition, which is characterized by an acute hypermetabolic state caused by excessive thyroid hormones. This medication is a non-selective beta-adrenergic antagonist that effectively manages the cardiovascular manifestations, such as tachycardia, hypertension, and palpitations that often accompany thyroid storm. By blocking the effects of catecholamines, propranolol helps in stabilizing the heart rate and provides symptomatic relief, which is crucial in the management of potentially life-threatening complications related to thyroid storm. In contrast, levothyroxine, which is a synthetic form of the thyroid hormone thyroxine (T4), would be contraindicated in this scenario as it would exacerbate hyperthyroidism and worsen the patient's condition. Metformin is an oral hypoglycemic agent, primarily used for the management of type 2 diabetes, and it does not have any role in the acute management of thyroid disorders. Insulin is primarily used to manage blood glucose levels and does not address the underlying causes or symptoms of hyperthyroidism or thyroid storm. Therefore, propranolol stands out as the drug of choice for controlling the immediate