MCQ – 90622

Correct Answer » C Explanation

• A growth hormone (GH)-secreting pituitary adenoma in an adult causes acromegaly.
• The pharmacological options for acromegaly include somatostatin analogues such as octreotide and GH receptor antagonists such as pegvisomant.
• The provided study material specifically identifies pegvisomant as a GH receptor antagonist indicated for the treatment of acromegaly.
• The high-yield drug table likewise lists pegvisomant as the specific drug for acromegaly.

Why Pegvisomant is correct:

• Pegvisomant is a growth hormone receptor antagonist.
• It blocks GH action at peripheral GH receptors, thereby reducing downstream insulin-like growth factor-1 (IGF-1) effects.
• It is therefore particularly useful for controlling the biochemical effects of excess GH in acromegaly.

Why the other options are less appropriate

A. Bromocriptine — Incorrect

• Bromocriptine is a dopamine D2 receptor agonist.
• Its major indication is hyperprolactinemia.
• It can also be used in acromegaly, but the supplied material notes that it is less effective than octreotide.
• Therefore, it is not the best answer when pegvisomant is available.

B. Octreotide — Incorrect 

• Octreotide is a somatostatin analogue that inhibits GH secretion.
• It is an important treatment for acromegaly and is specifically described in the supplied material as being used for acromegaly.
• However, the question is testing the characteristic drug pegvisomant, the GH receptor antagonist specifically indicated for acromegaly.

D. Goserelin — Incorrect

• Goserelin is a gonadotropin-releasing hormone (GnRH) analogue.
• Continuous administration suppresses luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
• It is used in conditions such as prostate cancer, endometriosis, uterine fibroids, and precocious puberty—not for GH excess.