Quick Facts
- Sample: Blood draw (serum)
- Fasting: No fasting required
- Turn-around: 1–2 business days. May take longer based on weather, holiday, or lab delays.
Benefits
- Direct access testing - No doctor's referral needed for convenient hormone screening
- Early detection - Identify adrenal disorders before they progress to serious complications
- Stress assessment - Measure your body's cortisol response to chronic stress conditions
- Fast results - Get confidential results in 1-2 days
- Affordable monitoring - Track ongoing adrenal health at lower cost than clinic visits
- Simple collection - Quick blood draw requiring only 1 mL of blood sample
Who Is This Test For?
- People experiencing chronic fatigue or unexplained energy changes
- Individuals with unexplained weight gain or loss despite normal diet
- Those managing chronic stress or suspected adrenal dysfunction symptoms
- Patients monitoring existing endocrine conditions like Addison's or Cushing's
- Health-conscious individuals seeking proactive hormonal health screening
- Anyone with symptoms of abnormal stress response or mood changes
How It Works – Just 3 Steps
- Order online - Purchase your test directly without a doctor's referral
- Visit lab location - Get a quick blood draw at any convenient lab site
- Receive results - Access secure results online in 1-2 days
FAQ
What does this test measure? Cortisol levels in your blood to assess adrenal gland function and stress hormone balance.
When is the best time to get tested? Morning testing (8 AM) is ideal due to natural cortisol fluctuations throughout the day.
What can affect my results? Stress, medications (steroids, estrogen), exercise, illness, and time of day can influence cortisol levels.
Do I need to prepare for this test? Avoid vigorous exercise 24 hours before testing; discuss medications with your healthcare provider.
How accurate is this test? Modern immunoassays provide high analytical sensitivity and specificity for cortisol measurement (Mayo Clinic 2023).
What happens if my results are abnormal? Consult your physician for further evaluation; additional tests like ACTH stimulation may be recommended.
More Details
What is the purpose of this test?
This test measures cortisol—a vital steroid hormone produced by your adrenal glands—to help diagnose disorders affecting the adrenal or pituitary glands. Cortisol regulates metabolism, blood pressure, immune response, and your body's stress reactions (Cleveland Clinic 2025). Abnormal levels can indicate conditions like Cushing syndrome (excess cortisol) or Addison disease (insufficient cortisol), allowing for early intervention and treatment.
Who would benefit from this test?
Individuals experiencing persistent fatigue, unexplained weight changes, abnormal stress responses, or symptoms suggestive of hormonal imbalance would benefit most from this testing (UCSF Health 2023). It's particularly valuable for those managing chronic stress, monitoring existing endocrine conditions, or seeking proactive wellness screening to detect hormone-related issues before they become serious health problems.
When should I order a Cortisol Blood Test (Random Serum)?
Order this test when experiencing persistent symptoms of adrenal dysfunction, as part of routine hormonal health monitoring, or when tracking ongoing endocrine conditions. It's recommended for individuals with unexplained fatigue, mood changes, weight fluctuations, or abnormal stress responses that don't improve with lifestyle changes (University of Rochester Medical Center 2025).
How do I interpret the results?
Cortisol Level: 6–23 mcg/dL (morning)
- What it means: Normal adrenal function
- Typical action: Continue routine monitoring
Cortisol Level: Below 6 mcg/dL
- What it means: Possible adrenal insufficiency
- Typical action: Further testing recommended
Cortisol Level: Above 23 mcg/dL
- What it means: Possible excess cortisol
- Typical action: Evaluate for Cushing syndrome
Cortisol Level: Borderline ranges
- What it means: May require repeat testing
- Typical action: Monitor symptoms, retest
Disclaimer: Reference ranges may vary by laboratory. Listed ranges are general guidelines and may differ from those used by the performing lab. Always consult your healthcare provider for interpretation.
Pre-test preparation
Ideally schedule your test for morning hours to account for natural cortisol fluctuations. Avoid vigorous exercise 24 hours before testing, as physical stress can elevate cortisol levels. Discuss with your healthcare provider about temporarily pausing interfering medications like steroids, estrogen, or certain supplements (UCSF Health 2023). Maintain your normal sleep schedule and try to minimize acute stress before testing.
How often should I get tested?
- Routine wellness screening: Annually or as needed
- Monitoring known adrenal disorders: Every 3–6 months
- Symptom evaluation: As directed by physician
- Medication adjustments: 4–6 weeks after changes
Why early detection matters
Prompt identification of adrenal insufficiency can prevent adrenal crisis—a life-threatening condition responsible for significant morbidity and healthcare utilization (University of Rochester Medical Center 2025). Early detection allows for timely treatment, preventing progression to more serious complications. Addison's disease affects approximately 100-140 individuals per million in the U.S., while Cushing syndrome is diagnosed in about 2-3 people per million annually (Cleveland Clinic 2025).
Related tests you may consider
ACTH (Adrenocorticotropic Hormone) Test- Pairing with cortisol testing helps distinguish primary from secondary adrenal disorders.
DHEA-S (Dehydroepiandrosterone Sulfate) Test - Provides broader insight into adrenal function and hormone balance.
24-Hour Urine Cortisol - Measures cortisol production over a full day for comprehensive assessment.
