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.
A doctor-written report.
Doctor-written reports and free doctor consultations on selected tests.
- Your blood test — processed by a UKAS-accredited UK laboratory.
- A doctor-written report — your results reviewed personally by Dr James Coleman, a practising GMC-registered GP, and explained in plain English.
- Clear next steps — what your results may mean, and what to do next where appropriate.
- Optional GP appointment — want to talk it through? You can book a private appointment to discuss your results.
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.
- Doctor-reviewed report
- Free tracked delivery
- Results in 2–3 working days
- Actionable next steps

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 is dispatched and on its way to you.
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 doctor-written report
Reviewed by a practising doctor. Delivered to your secure portal within 2–3 working days.
Follow-up if you need it
If anything in your report needs discussing, you can request a follow-up with our GP from your account — free, and entirely optional.
Your results, explained in 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
Written interpretation, not a PDF
Your results come with Dr Coleman's written interpretation — what each marker means and what to do about it, in plain English.
doctor-written report included
Every report is written by Dr Coleman, a practising GP — not auto-generated and not outsourced.
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
Is my report reviewed by a doctor?
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?
Drop us a message — a real person will reply.
We usually get back within one working day. Anything you want to ask before ordering — collection, what's included, fasting, your report, results timing — go ahead.
Ready to order?
A simple sample, a UKAS-accredited lab, and a doctor-written report personally interpreted by Dr Coleman.
Order my Cortisol →