Description
Capture Your Body’s Natural Cortisol Peak
Cortisol is a vital hormone produced by the adrenal glands that follows a diurnal rhythm—peaking shortly after waking and dipping to its lowest point at night. Measuring cortisol in the morning (within 2 hours of awakening) provides a reliable snapshot of adrenal function and helps diagnose disorders of over- or under-production.
Clinical Uses
- Diagnosing Adrenal Insufficiency (Addison’s disease)
- Screening for Cushing’s Syndrome (excess cortisol)
- Evaluating Chronic Fatigue or Unexplained Weight Changes
- Assessing HPA Axis Disorders (hypothalamic-pituitary-adrenal dysfunction)
- Monitoring Treatment for known adrenal or pituitary conditions
Test Details & Patient Prep
- Specimen Type: Venous blood draw
- Timing: Within 2 hours of waking—ideally between 6 AM and 9 AM
- Preparation:
- No fasting required
- Avoid strenuous exercise, caffeine, and high-stress activities before the draw
- Note exact wake-up and draw times for accurate interpretation
Because cortisol fluctuates widely over 24 hours, an A.M. specimen establishes the baseline peak. Abnormally low or high values at this time warrant further testing—such as late-night salivary cortisol or dexamethasone suppression—to explore diurnal variation and feedback mechanisms.
