Cortisol (Urine) Test | London Blood Tests UK

Measure daily cortisol output with our Urine Cortisol Test from £99. UKAS-accredited analysis, accurate adrenal assessment, optional GP consultation.

The Cortisol (Urine) Test measures cortisol excreted in urine to assess overall daily cortisol production and adrenal gland function. Priced at £99, this test is analysed in a UKAS-accredited laboratory, with results typically available within 7–10 business days and an optional GP consultation for interpretation.

What is a Cortisol (Urine) Test?

Cortisol is a steroid hormone produced by the adrenal glands in response to stress and regulated by the hypothalamic-pituitary-adrenal (HPA) axis. It plays a critical role in blood pressure regulation, metabolism, immune response, and stress adaptation.

Unlike blood or saliva cortisol tests that reflect cortisol levels at a specific moment in time, the urine cortisol testmeasures the total amount of cortisol excreted over a defined period, most commonly a 24-hour urine collection. This provides a more comprehensive picture of overall cortisol output across the day and night.

Urine cortisol testing is particularly valuable for investigating chronic cortisol excess or deficiency, including suspected Cushing’s syndrome, adrenal hyperactivity, or prolonged physiological stress. Because cortisol secretion follows a circadian rhythm, a urine test avoids the limitations of single-time-point blood sampling.

Benefits of the Cortisol (Urine) Test

1. Measures Total Daily Cortisol Output
   Captures cumulative cortisol production rather than a single snapshot, offering a more accurate assessment of adrenal activity.

2. Gold Standard for Cushing’s Syndrome Screening
   Widely used in the investigation of cortisol excess and adrenal hyperfunction.

3. Not Affected by Circadian Timing
   Eliminates variability caused by time-of-day sampling seen with blood or saliva tests.

4. Useful for Chronic Stress Assessment
   Helps identify prolonged physiological stress that may not be detected with spot testing.

5. Supports Adrenal Function Investigation
   Assists in diagnosing adrenal disorders and evaluating abnormal cortisol regulation.

6. Non-Invasive and Convenient
   Requires urine collection only, avoiding repeated blood draws.

7. Optional GP Consultation for Interpretation
   Results can be reviewed with a GP to interpret findings and determine whether further endocrine testing is needed.

Why Do I Need a Cortisol (Urine) Test?

You may benefit from this test if you have symptoms or clinical concerns related to abnormal cortisol levels, such as:

• Persistent fatigue or weakness

• Weight gain, particularly around the abdomen

• Easy bruising or thin skin

• High blood pressure difficult to control

• Mood changes, anxiety, or depression

• Muscle weakness

• Poor sleep or disrupted circadian rhythm

• Unexplained metabolic changes

This test is commonly requested when investigating:

• Suspected Cushing’s syndrome

• Adrenal gland disorders

• Chronic stress-related symptoms

• Abnormal cortisol results from blood or saliva tests

How the Test Works

At-Home Urine Collection (Standard Method)

1. Order Your Test

   • Order online with no referral required.

   • You’ll receive a urine collection kit with full instructions.

2. Collection Preparation

   • The test usually requires a 24-hour urine collection.

   • Avoid excessive exercise, alcohol, and certain medications if advised.

3. Urine Collection

   • Discard the first urine sample in the morning.

   • Collect all urine for the next 24 hours, including the first sample the following morning.

4. Sample Storage

   • Keep the collection container refrigerated or in a cool place during the collection period.

5. Sample Return

   • Once complete, seal the container and return it using the prepaid packaging.

6. Laboratory Analysis

   • Cortisol is measured using validated immunoassay or mass spectrometry methods.

7. Results Delivery

   • Results are typically available within 7–10 business days.

8. Optional GP Consultation

   • A GP can review your results and advise on further testing or management.

Your Cortisol (Urine) Results – Explained

Urinary cortisol is usually reported as micrograms per 24 hours (µg/24h) or nanomoles per day (nmol/day).

Typical UK Reference Ranges

• Normal: 20–90 µg/24h

• Borderline high: 90–120 µg/24h

• High: >120 µg/24h (suggestive of cortisol excess)

• Low: <20 µg/24h (may suggest adrenal insufficiency)

Interpretation Guidance

• Elevated cortisol may indicate chronic stress, adrenal hyperfunction, or Cushing’s syndrome.

• Low cortisol may suggest adrenal insufficiency or suppressed adrenal activity.

• Results should always be interpreted alongside symptoms and, where necessary, confirmed with blood, saliva, or imaging studies.

An optional GP consultation can help determine whether further endocrine testing (e.g., dexamethasone suppression test or ACTH measurement) is required.