What Is Stress Chemical Imbalance?

Imbalance within the stress response system primarily involves dysregulation of the hypothalamic-pituitary-adrenal axis (HPA). In effect, cortisol is produced in either abnormally low or excessive quantities, depending on etiology.

Normal Physiology

• In initial response to various stressors, the hypothalamus and pituitary release regulatory hormones which stimulate adrenal release of cortisol, epinephrine and norepinephrine. Once the alarm phase is terminated, epinephrine and norepinephrine return to normal levels while cortisol remains elevated for some time. When this secondary resistance reaction is no longer necessary, cortisol production is also downregulated to pre-stress capacity.

HPA Hyperactivity

• In HPA axis disturbance of this nature, there is overproduction of the hormone CRH and cortisol, independent of any actual stress. This may give rise to mood disturbances, depressed immunity, insomnia, loss of appetite, decreased libido, hypertension, weight gain and dyslipidemia.

HPA Suppression

• Diminished HPA activity is characterized by decreased levels of both CRH and cortisol as well as a muted overall stress response. Some of the symptoms of insufficient cortisol levels can be remarkably similar to those of its excess but can additionally manifest as fibromyalgia, inflammatory conditions and inappropriate immune reactions.

Etiology

• Multiple factors can disrupt HPA, including adrenal hyperplasia, pituitary adenoma, cytotoxic agents, enzyme inhibitors, continuous corticosteroid use, autoimmune diseases and prolonged stress.

Diagnosis

• To investigate suspected HPA malfunction, cortisol, DHEA, and ACTH concentrations are routinely assessed. Adrenal cortical ACTH sensitivity and dexamethasone suppression tests are also utilized.