What is adrenal fatigue in the context of a patient with potential hypothyroidism and symptoms of fatigue, weight gain, and difficulty sleeping?

"Adrenal Fatigue" Is Not a Real Medical Condition

"Adrenal fatigue" is a myth with no scientific basis—it is not recognized by any endocrinology society and has been systematically disproven by research. 1

What Patients Are Actually Experiencing

When patients present with symptoms attributed to "adrenal fatigue" (fatigue, weight gain, difficulty sleeping), they may have:

Legitimate Medical Conditions to Evaluate

Hypothyroidism is the most likely culprit in your clinical scenario and should be thoroughly evaluated first 2, 3:

• Check TSH and free T4 to diagnose overt or subclinical hypothyroidism 3
• Hypothyroidism causes fatigue (50-95% of cases), weight gain, and sleep disturbances 4
• Treatment with levothyroxine resolves these symptoms in most patients 3

True adrenal insufficiency (not "adrenal fatigue") is a rare but serious condition 4:

• Affects less than 279 per 1 million individuals 4
• Diagnosed by early-morning cortisol (<5 µg/dL), elevated ACTH, and low DHEAS in primary AI 4
• Presents with fatigue, nausea/vomiting (20-62%), and weight loss (43-73%)—note weight LOSS, not gain 4
• Requires hydrocortisone replacement therapy, not the unproven supplements marketed for "adrenal fatigue" 4

Glucocorticoid-induced adrenal insufficiency is common but only occurs after supraphysiological glucocorticoid exposure 4:

• Suspect only in patients recently tapering or discontinuing high-dose steroids 4
• Diagnosed with low/intermediate morning cortisol (5-10 µg/dL) and low-normal ACTH 4

Why "Adrenal Fatigue" Is Pseudoscience

A systematic review of 58 studies examining 3,470 articles found no substantiation that "adrenal fatigue" exists as a medical condition 1:

• Studies showed conflicting and contradictory results regardless of methodology 1
• Cortisol levels do not correlate with fatigue severity in properly conducted studies 1, 5
• Even in patients with confirmed adrenal insufficiency, salivary cortisol levels were not correlated with momentary fatigue 5

The concept relies on unvalidated cortisol testing methods not endorsed by endocrinologists 1.

Critical Diagnostic Approach for Your Patient

For a patient with fatigue, weight gain, and sleep disturbance:

1. Check thyroid function first 3:

   • Measure TSH and free T4 3
   • If TSH >10 mIU/L, initiate levothyroxine regardless of symptoms 3
   • If TSH 4.5-10 mIU/L with symptoms, consider treatment trial 3

2. Evaluate for true adrenal insufficiency only if clinically indicated 4:

   • Early-morning (8 AM) cortisol, ACTH, and DHEAS 4
   • Indicated if: hypotension, hyponatremia, hyperpigmentation, or recent steroid use 4
   • NOT indicated for nonspecific fatigue alone 1

3. Consider other legitimate causes 6:

   • Depression and psychiatric disorders (often overlap with hypothyroid symptoms) 6
   • Sleep disorders (sleep apnea, insomnia) 2
   • Chronic fatigue syndrome (has specific diagnostic criteria, not "adrenal fatigue") 7
   • Metabolic abnormalities (diabetes, dyslipidemia) 6

Common Pitfalls to Avoid

Do not order salivary cortisol panels or "adrenal stress tests" marketed for "adrenal fatigue" 1:

• These tests use unsubstantiated methodology 1
• Results do not correlate with clinical symptoms 1, 5
• They lead to inappropriate treatment with unproven supplements 1

Do not miss hypothyroidism by accepting "adrenal fatigue" as the diagnosis 3:

• Hypothyroidism is common and treatable 3
• Symptoms overlap completely with those attributed to "adrenal fatigue" 2, 3
• TSH is highly sensitive (>98%) and specific (>92%) for thyroid dysfunction 3

Do not confuse chronic fatigue syndrome with "adrenal fatigue" 7:

• Chronic fatigue syndrome has specific diagnostic criteria 2
• It may involve mild HPA axis dysfunction, but this is NOT "adrenal fatigue" 7
• Treatment does not involve adrenal supplements 2

In patients with suspected central hypothyroidism, always rule out adrenal insufficiency before starting thyroid hormone 2:

• Starting levothyroxine before corticosteroids can precipitate adrenal crisis 2
• This applies to true adrenal insufficiency, not mythical "adrenal fatigue" 4