Doctor's Assessment Included
Every result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.
Creatinine: Normal Values and What a High Result Means
Creatinine monitoring is essential for healthy ageing, as kidney function naturally declines with age. Older adults may also be more susceptible to medication-related kidney effects, making regular creatinine testing an important part of age-appropriate health screening.
Results within 1–3 working days after your blood draw (estimate)
Reference Ranges
Reference ranges may vary between laboratories. When you order a test, a BIG-registered doctor assesses your personal results in context. For treatment decisions, discuss your results with your GP.
Check your own valueWhat It Measures
This test measures the concentration of creatinine in your blood. Creatinine is produced at a relatively constant rate from the breakdown of creatine phosphate in muscle tissue and is almost entirely filtered by the kidneys.
Because its production rate is generally stable, rising blood creatinine levels typically indicate that the kidneys are not filtering as efficiently as they should. It is one of the most commonly used markers in routine kidney function assessment.
Why It Matters
Creatinine is central to assessing kidney health. It is used to calculate the estimated glomerular filtration rate (eGFR), which is the primary measure for staging chronic kidney disease.
Early detection of rising creatinine levels can prompt timely intervention, helping to slow the progression of kidney damage. Monitoring creatinine is also important for adjusting medication dosages, as many drugs are cleared by the kidneys.
When to Test
Creatinine testing is a standard component of routine blood work and comprehensive metabolic panels. It is particularly important for individuals with diabetes, high blood pressure, or a family history of kidney disease.
More frequent testing may be recommended for those taking medications that can affect the kidneys, or for individuals who have been diagnosed with any stage of chronic kidney disease.
Symptoms
Low Levels
Unintended weight loss
Fatigue and general weakness
High Levels
Swelling in the face, ankles, or feet
Nausea or loss of appetite
Decreased urine output or changes in urination
Muscle cramps
Recommendations
Male
Low creatinine may indicate reduced muscle mass. Consider evaluation if unexpected.
Elevated creatinine may indicate kidney dysfunction. Consult your healthcare provider for kidney function evaluation.
Female
Low creatinine may indicate reduced muscle mass. Consider evaluation if unexpected.
Elevated creatinine may indicate kidney dysfunction. Consult your healthcare provider for kidney function evaluation.
Lifestyle Tips
Maintain adequate hydration to support optimal kidney filtration. Avoid excessive protein supplementation, as very high protein intake can temporarily raise creatinine levels.
Manage chronic conditions such as diabetes and hypertension carefully, as these are the leading causes of kidney damage. Limit the use of NSAIDs and other potentially nephrotoxic substances, and discuss all supplements with your healthcare provider.