FPGEE for National Association of Boards of Pharmacy (NABP) Practice Exam 2025 - Free NABP Practice Questions and Study Guide

In secondary adrenal insufficiency, the main issue lies in the pituitary gland's inability to produce adequate amounts of adrenocorticotropic hormone (ACTH). Since ACTH is responsible for stimulating the adrenal glands to produce cortisol, a decrease in ACTH leads to insufficient cortisol production.

In this scenario, the adrenal glands themselves are functioning properly, but due to the low levels of ACTH, cortisol production is diminished. This results in a feedback mechanism where, because cortisol levels are low, the adrenal gland doesn't receive the stimulation necessary to produce more cortisol. However, it's important to understand that the feedback inhibition of the hypothalamus also plays into this dynamic because low cortisol levels lead to less corticotropin-releasing hormone (CRH) being secreted, further contributing to reduced ACTH levels.

The other choices do not accurately describe the hormonal changes occurring in secondary adrenal insufficiency. While aldosterone secretion can sometimes be maintained relatively well due to the renin-angiotensin system, it is not directly influenced by ACTH and is not a primary concern in this context. Growth hormone levels are also independent of ACTH and do not typically show changes due to secondary adrenal insufficiency. Thus, the primary change associated with this condition is the