Cortisol
Are you constantly feeling drained, wired and tired, or struggling to wake up refreshed? This blood test measures cortisol, your body's primary stress hormone, helping you understand what's driving your fatigue and take informed next steps.
Choose how you'd like your sample taken
Pick the option that suits you. The test is the same — only the way we collect your sample changes.
- GP-written interpretation by Dr James Coleman
- UKAS-accredited UK laboratory
- Results in 2–3 working days
No subscription. No hidden fees. Same-day dispatch. Ordering more than one test? Place each order separately — each one ships as its own kit with its own doctor's report.

Dr James Coleman
“Every Brooksby report is written personally. You get a plain-English interpretation and a clear next step — not just numbers on a page.”
Simple from start to finish
Order your test
Choose online in minutes. Your kit ships the same working day.
Collect your sample
Finger-prick or Venous collection
Post it back
Drop your pre-paid, tracked envelope in any postbox. We take it from there.
Your GP-written report
Reviewed by a practising GP. Delivered to your secure portal within 2–3 working days.
Book your doctor review
Receive a link to book a private call with your doctor to discuss your results and the next steps that make sense for you.
Every result comes with a written report
What you actually get in this test
1 marker analysed by a UKAS-accredited UK laboratory.
A GP-led service, not a lab with a website
GP-written report included
Every report is written by Dr Coleman, a practising GP. No extra charge.
A named doctor, not a team
Your report is signed by Dr Coleman personally. Not an anonymous review pool.
UKAS-accredited UK lab
Same accreditation standard used by NHS hospitals. Consistent, reliable analysis.
One-off, no subscription
You order the test, you get the report, you own the data. No ongoing fees.
Common questions
Everything you need to know before ordering your Cortisol.
What does a cortisol blood test measure?
This test measures the level of cortisol in your blood. Cortisol is your body's main stress hormone, produced by the adrenal glands. It plays a key role in regulating energy, metabolism, inflammation and your sleep-wake cycle.
Who should consider a cortisol test?
This test is useful for:
Anyone experiencing persistent fatigue or burnout
Those feeling wired but exhausted
People with disrupted sleep patterns
Anyone with unexplained weight changes, particularly around the midsection
When should I take this test?
Cortisol follows a natural daily rhythm, peaking in the early morning and falling throughout the day. For the most clinically useful result, collect your sample between 8 and 10 AM.
Do I need to fast for a cortisol test?
No fasting is required. However, avoid strenuous exercise on the morning of the test as this can temporarily raise cortisol levels.
How will I receive my results?
Secure online results with a GP-written explanation from Brooksby Medical in 2 to 3 working days.
More about Brooksby
How accurate are the results?
Who writes the reports?
How long do results take?
Do I need a GP referral?
Can I share my results with my NHS GP?
What happens if something is abnormal?
What is the difference between venous and fingerprick?
Is my data kept private?
Ready to order?
A simple sample, a UKAS-accredited lab, a GP-written report with clear next steps.
Order my Cortisol →
