Cortisol Blood Test: Meaning, Levels, and Interpretation
A cortisol blood test measures the level of cortisol, the body's main stress hormone. Normal morning levels typically range from 5 to 23 mcg/dL in adults. High cortisol levels may indicate chronic stress or Cushing's syndrome, while low levels suggest adrenal insufficiency. This test helps evaluate adrenal and pituitary gland function.
Contents
Result interpretation Cortisol
What your result means based on common reference ranges
Cortisol levels within range indicate proper adrenal and pituitary function supporting metabolic balance and stress response.
Mildly elevated cortisol levels often reflect acute stress, exercise, or pregnancy without underlying endocrine disorder involvement.
Significantly high cortisol levels suggest Cushing's syndrome or endocrine dysfunction with sustained overproduction affecting metabolism and blood pressure.
Low cortisol levels indicate adrenal insufficiency such as Addison's disease, impairing energy regulation and cardiovascular stability.
🔬 Check your value Cortisol
Enter your result and get a personalized interpretation
What is Cortisol?
Cortisol is a steroid hormone produced by the adrenal glands and regulated by the hypothalamic-pituitary-adrenal axis. It plays a central role in metabolism, blood pressure control, and immune response. A cortisol blood test reflects how the body responds to stress and maintains energy balance. Abnormal cortisol levels are linked to conditions such as Cushing's syndrome, Addison's disease, and insulin resistance. Because cortisol follows a daily rhythm, timing of the blood test is critical for accurate interpretation of results.
Reference ranges
Causes of abnormal values
Causes of low Cortisol
- • Addison's disease: adrenal gland damage reduces hormone production
- • Pituitary insufficiency: reduced ACTH limits cortisol release
- • Sudden steroid withdrawal: adrenal suppression prevents recovery of natural production
- • Chronic adrenal fatigue states: prolonged dysfunction lowers baseline cortisol
Causes of high Cortisol
- • Chronic stress: prolonged activation increases cortisol production
- • Cushing's syndrome: adrenal or pituitary dysfunction causes excess hormone secretion
- • Pituitary tumors: excess ACTH stimulates adrenal overproduction
- • Steroid medications: external glucocorticoids elevate measured cortisol levels
- • Estrogen therapy: increases cortisol-binding proteins in blood
- • Severe illness or trauma: physiological stress response elevates cortisol
Cortisol in combination with other markers
Possible symptoms
- •Rapid weight gain in abdomen and face
- •Muscle weakness and fatigue
- •High blood pressure
- •Skin thinning and stretch marks
- •Dizziness or low blood pressure
- •Unintentional weight loss
When to see a doctor
Consult a doctor if cortisol levels are below 3 mcg/dL or significantly above the normal range. Seek evaluation if symptoms such as rapid weight gain, persistent fatigue, or low blood pressure occur. Repeated abnormal results or worsening symptoms require endocrine assessment.
What to do if abnormal
- Repeat test under proper conditions (morning, rested state)
- Consult an endocrinologist for detailed hormonal evaluation
- Review medications, especially steroids or hormone therapies
- Monitor blood pressure and blood glucose regularly
- Improve sleep and reduce stress before retesting
The information on this page is intended for general understanding of test results and does not replace medical consultation. Accurate interpretation requires considering other blood markers and individual factors.
Content is based on medical literature and used within the PulseBook analytical system.
Want to understand your full health picture?
PulseBook analyzes all your results together, remembers your history and answers questions 24/7
Try for free →Fast • Sign in with Google • Free