Urine free cortisol (24 hour)
What this test measures
The total unbound cortisol passed in urine over a day. Because it averages the whole day, it is one of the screening tests for cortisol excess.
Why doctors request it
Endocrinologists request it when Cushing's syndrome is being considered, usually two or three collections.
What commonly pushes it up
- Cortisol excess from any cause
- Severe stress, depression or alcohol excess
- Over-collection
- Some medicines as a class
What commonly pushes it down
- An incomplete collection
- Kidney disease
Everyday reasons for a value outside the range
- Collection errors are common, so it is repeated
- Ranges depend on the laboratory method
About the sample
Every drop for exactly 24 hours, kept cool.
Upload a photo or PDF and see every line against the range your lab printed, explained in plain English. First report free.
Read my report freeThis is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.