What is adrenal fatigue?

Adrenal Fatigue Is Not a Recognized Medical Condition

"Adrenal fatigue" is a term used in alternative medicine to describe a collection of nonspecific symptoms allegedly caused by chronic stress, but it is not recognized as a legitimate medical diagnosis by any endocrinology society and lacks scientific evidence to support its existence. 1

What the Term Claims to Describe

The concept of "adrenal fatigue" suggests that chronic exposure to stressful situations causes the adrenal glands to become "exhausted" and unable to produce adequate amounts of hormones, particularly cortisol. 1 Proponents claim this leads to symptoms such as:

• Persistent fatigue and lack of energy 1, 2
• Difficulty waking up in the morning 2
• Salt and sugar cravings 2
• Difficulty handling stress 2
• Decreased libido 2
• Mild depression 2

Why It Is Not a Valid Diagnosis

A systematic review examining 58 studies (33 in healthy individuals and 25 in symptomatic patients) found no substantiation that "adrenal fatigue" is an actual medical condition. 1 The review identified critical flaws in the research claiming to support this diagnosis:

• Conflicting and inconsistent results across studies using various cortisol assessment methods 1
• Unsubstantiated methodology for cortisol testing not endorsed by endocrinologists 1
• Poor quality assessment of fatigue symptoms 1
• Invalid conclusions regarding causality between cortisol levels and fatigue 1
• Heterogeneous study designs that prevent meaningful interpretation 1

The Real Medical Condition: Adrenal Insufficiency

What does exist is adrenal insufficiency, a legitimate and serious medical condition that is entirely different from the mythical "adrenal fatigue." 3, 4

Key Differences

Adrenal insufficiency is characterized by:

• Objective hormonal deficiency: Morning cortisol <5 µg/dL in primary adrenal insufficiency, or 5-10 µg/dL with low ACTH in secondary forms 3
• Specific diagnostic criteria: Confirmed by early-morning cortisol, ACTH, and DHEAS measurements, plus cosyntropin stimulation testing when needed 3, 5
• Life-threatening potential: Can progress to adrenal crisis with hypotension, shock, and death if untreated 6, 7
• Clear pathophysiology: Caused by autoimmune destruction, congenital disorders, infections, tumors, or prolonged glucocorticoid therapy 3

In contrast, "adrenal fatigue":

• Has no validated diagnostic test 1
• Shows no consistent cortisol abnormalities 1
• Is not recognized by the Endocrine Society or any major medical organization 1
• Cannot be distinguished from normal fatigue through careful diagnostic evaluation 8

Clinical Implications and Pitfalls

Critical Warning

The danger of the "adrenal fatigue" diagnosis is that it may delay recognition of true adrenal insufficiency, which requires immediate treatment to prevent adrenal crisis and death. 6, 7

When to Suspect Real Adrenal Insufficiency

Evaluate for genuine adrenal insufficiency when patients present with:

• Unexplained hypotension, especially orthostatic changes 6
• Hyponatremia (present in 90% of cases) 5, 6
• Hyperkalemia (present in ~50% of cases) 5, 6
• Hyperpigmentation of skin (in primary adrenal insufficiency) 6
• Nausea and vomiting (20-62% of cases) 5, 3
• Weight loss (43-73% of cases) 3
• History of glucocorticoid use (most common cause of adrenal insufficiency) 3

Proper Diagnostic Approach

If adrenal insufficiency is suspected:

1. Obtain early-morning (8 AM) measurements of serum cortisol, ACTH, and DHEAS 5, 3
2. Check basic metabolic panel for sodium, potassium, and glucose 5
3. Perform cosyntropin stimulation test if morning cortisol is 5-10 µg/dL (indeterminate range) 5, 3
4. Never delay treatment if adrenal crisis is suspected—give hydrocortisone 100 mg IV immediately plus 0.9% saline at 1 L/hour 6, 5

Bottom Line

"Adrenal fatigue" is a myth perpetuated in alternative medicine without scientific basis. 1 Patients presenting with chronic fatigue require proper medical evaluation to identify treatable causes, including—but not limited to—true adrenal insufficiency, thyroid disorders, depression, sleep disorders, anemia, and chronic diseases. 8, 3 The term "adrenal fatigue" should be abandoned in favor of evidence-based diagnoses that can guide appropriate treatment.