UK kidney health guideCreatinine Blood Test in the UK: What High or Low Results Can Mean
Creatinine is a waste product produced largely through normal muscle metabolism. The kidneys remove creatinine from the blood, so a blood creatinine test is commonly used when assessing kidney function.
Creatinine is important, but the number should not be interpreted in isolation.
Why is creatinine measured?
A creatinine result can be used as part of kidney function assessment and is also used in calculations such as eGFR. Healthcare professionals may compare the result with previous measurements to identify changes.
What can affect creatinine?
Muscle mass, age, diet, exercise, hydration and some medicines can influence creatinine. A person with more muscle may naturally have a higher creatinine than someone with less muscle.
This is one reason why clinicians use eGFR and the wider clinical picture rather than relying on creatinine alone.
Does a high creatinine always mean kidney failure?
No. A high result can have different causes, including reduced kidney filtration, changes in hydration, medication effects or other medical circumstances. A clinician needs to interpret the result in context.
Likewise, a normal creatinine does not necessarily exclude early kidney disease.
Creatinine and eGFR
The two measurements are related, but they are not interchangeable. A creatinine result can be used to calculate eGFR (try our eGFR calculator), while urine testing provides additional information about kidney damage.
If your creatinine has changed significantly from your previous result, ask your healthcare professional whether repeat testing or further investigation is needed.
Nisarg Ayurveda's educational material can help you prepare questions for a consultation. It should not be used to self-diagnose or to change prescribed medicines.
Why a specific creatinine number can't be looked up on its own
If you've been given a specific creatinine result and searched for what that exact number means, it helps to know why a simple lookup isn't reliable for this particular test:
UK labs report creatinine in µmol/L, not mg/dL
If you've seen a decimal figure like "1.1" or "2.0" online, that's typically the US mg/dL convention. UK blood tests report creatinine in micromoles per litre (µmol/L), usually a whole number such as 70, 90 or 150. Check the units on your own results before comparing to anything you read online.
Why the "normal range" varies by lab
Reference ranges differ between laboratories, and also by sex, age and muscle mass — a muscular person can have a higher baseline creatinine without any kidney problem. Your results should always be compared against the reference range printed on your own report, not a generic figure online.
Creatinine alone isn't the full picture
Creatinine is one input used to estimate eGFR, which is the figure clinicians use for CKD staging. See our eGFR guide for how specific eGFR values map to CKD stages — that's usually the more useful number to discuss with your GP.
What to do with your result
Compare it with your previous results and the reference range on your report, and discuss any change with your GP or kidney specialist rather than interpreting the number alone.
Want to discuss your situation?
Nisarg Ayurveda offers complementary Ayurvedic consultation support. Bring your relevant medical reports and medication list to the consultation. This service does not replace GP, nephrology or emergency care.