At what time are peak levels of adrenocorticotropic hormone typically expected to occur?

Adrenocorticotropic hormone (ACTH) is primarily responsible for stimulating the adrenal glands to produce cortisol, which is part of the body's response to stress and follows a diurnal rhythm. Peak levels of ACTH are typically found in the early morning, aligned with the body's natural circadian rhythms. Most individuals experience the highest concentrations of ACTH between 6 AM and 9 AM. This timing coincides with the natural rise in cortisol, which prepares the body for the activities of the day.

The circadian rhythm, influenced by the sleep-wake cycle, dictates that hormone levels fluctuate throughout the day, with ACTH and cortisol both peaking in the morning and declining throughout the day. Understanding this timing is crucial in contexts such as diagnosing adrenal disorders, managing stress-related conditions, or administering medications that affect hormonal balance.