Which among the following statements is wrong ?
**Core Concept**
The question revolves around the pathophysiology and treatment of pheochromocytoma, a rare catecholamine-secreting tumor that can lead to hypertension, tachycardia, and other cardiovascular complications. The underlying concept involves the role of catecholamines, such as epinephrine and norepinephrine, and their interaction with adrenergic receptors.
**Why the Correct Answer is Right**
Option C states that phenoxybenzamine is a non-selective alpha-blocker used in the management of pheochromocytoma. This is correct because phenoxybenzamine works by irreversibly blocking alpha-1 and alpha-2 adrenergic receptors, which are responsible for the vasoconstrictive effects of catecholamines. This blockade allows for the reduction of blood pressure and heart rate, making it an essential component of pheochromocytoma management.
**Why Each Wrong Option is Incorrect**
**Option A:** This statement is incomplete and cannot be evaluated.
**Option B:** This option is missing, so we cannot evaluate it.
**Option D:** This option is also missing, so we cannot evaluate it.
**Clinical Pearl / High-Yield Fact**
When managing pheochromocytoma, it is essential to use alpha-blockers such as phenoxybenzamine to control blood pressure before administering beta-blockers, as unopposed beta-blockade can lead to a paradoxical increase in blood pressure and heart rate.
**Correct Answer: C. Phenoxybenzamine is a non-selective alpha-blocker used in the management of pheochromocytoma.**