A man diagnosed with phaeochromocytoma exhibits hypertension and sweating. What is the most suitable initial medication?

In the management of phaeochromocytoma, which is characterized by the overproduction of catecholamines (such as epinephrine and norepinephrine) from adrenal medullary tumors, the foremost concern is controlling hypertension, as well as other sympathetic overactivity symptoms like sweating.

The most suitable initial medication in this scenario is an alpha-blocker. Alpha-adrenergic antagonists effectively counteract the excessive vasoconstriction caused by catecholamines, thereby helping to lower blood pressure and alleviate symptoms related to excess sympathetic stimulation. Starting treatment with an alpha-blocker is crucial to manage hypertensive episodes and prevent complications related to severe hypertension.

Using an alpha-blocker as a first-line treatment ensures that the underlying cause of the hypertension is addressed directly, which is critical in a condition such as phaeochromocytoma. The proper role of an alpha-blocker is paramount in stabilizing blood pressure before any other treatments are initiated, such as surgical intervention for tumor removal.

The other options listed would not address the immediate hypertensive crisis effectively or may have contraindications in this specific context. For example, tricyclic antidepressants are not indicated for hypertension management and could worsen blood pressure instability. Diazepam, which is primarily