Which of the following medications should be used for pheochromocytoma associated hypeension after phenoxybenzamine is staed?
**Core Concept**
Pheochromocytoma is a rare tumor of the adrenal gland that produces excess catecholamines, leading to hypertension. The management of pheochromocytoma-associated hypertension involves the use of specific medications to control blood pressure before surgery. **Phenoxybenzamine** is an alpha-blocker used as the initial medication to control hypertension by blocking alpha-adrenergic receptors.
**Why the Correct Answer is Right**
After starting **phenoxybenzamine**, a beta-blocker should be added to control the tachycardia that can occur due to the blockade of alpha-receptors. This is because **beta-blockers** inhibit the effects of excess catecholamines on the heart, reducing heart rate and contractility.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it is not specified, but typically, beta-blockers are added after alpha-blockade is established.
**Option B:** Incorrect as it is not typically the next step after initiating phenoxybenzamine.
**Option C:** Incorrect because it is not usually the next medication added after phenoxybenzamine.
**Option D:** Incorrect, but the correct answer is not provided to directly address this option.
**Clinical Pearl / High-Yield Fact**
A crucial point to remember is that **beta-blockers** should never be started before **alpha-blockers** in the management of pheochromocytoma, as this can lead to a hypertensive crisis due to unopposed alpha-adrenergic receptor stimulation.
**Correct Answer:** D. Beta-blocker.