Does Creatinine Affect Your Kidneys?
If you've recently had a blood test showing raised creatinine levels, or are curious about how creatinine relates to kidney health, understanding what this marker means could be key to protecting your long-term wellbeing.
Creatinine is a waste product that is excreted by the kidneys. Elevated levels of creatinine in your blood may be an early sign that your kidneys aren't functioning as efficiently as they should be. Regular blood testing can help identify changes in kidney function before symptoms appear.
Below, we explore what creatinine is, how it impacts the kidneys and how a simple blood test could help you take control of your health.
What is creatinine?
Creatinine is a chemical waste product that forms when creatine, a substance that helps supply energy to your muscles, is broken down. This waste product enters your bloodstream and is filtered out by your kidneys.
In healthy individuals, creatinine is removed from the blood efficiently and passed out of the body in urine. However, if the kidneys are not working properly, creatinine levels can start to rise in the blood, as it is not being cleared effectively.
How does creatinine affect the kidneys?
While creatinine itself doesn't harm your kidneys, it acts as a reliable indicator of how well they are working. In other words, creatinine doesn't cause kidney problem; it helps detect them.
If blood tests reveal high levels of creatinine, this could suggest that your kidneys are not filtering waste as they should. Persistently raised creatinine levels often prompt further investigation into kidney function and may point to conditions such as:
-
Chronic kidney disease (CKD)
-
Acute kidney injury (AKI)
-
Dehydration
-
Muscle disorders
-
Urinary tract obstructions
Low creatinine levels are far less common but may occur in people with low muscle mass, advanced liver disease or during pregnancy.
How can I check my creatinine levels?
Creatinine levels are measured through a simple blood test known as a serum creatinine test. This test is commonly included as part of a kidney function panel or renal profile, and it may be recommended if you're experiencing symptoms of kidney disease or as part of a general health check.
For a more detailed understanding of kidney function, your doctor or health provider may also calculate your estimated glomerular filtration rate (eGFR). This calculation uses your creatinine level along with age, sex and body size to estimate how well your kidneys are filtering blood.
At Bluecrest Wellness, our private blood tests offer convenient and reliable insights into your kidney health, including serum creatinine and eGFR as part of our comprehensive health assessments.
Why should I monitor creatinine levels?
Monitoring your creatinine levels regularly can help identify potential issues with your kidneys before more serious symptoms develop. This is especially important if you:
-
Have a family history of kidney disease
-
Are living with diabetes or high blood pressure
-
Are taking medications that may affect kidney function
-
Have had abnormal kidney test results in the past
-
Are over the age of 60
Symptoms of high creatinine
In the early stages, high creatinine may not cause noticeable symptoms. However, as kidney function declines, you may begin to experience:
-
Fatigue
-
Swelling in the legs or ankles
-
Nausea or vomiting
-
Changes in urination (less frequent or foamy urine)
-
Shortness of breath
-
Confusion or difficulty concentrating
-
High blood pressure
If you’re experiencing any of these symptoms, it’s important to speak to a healthcare professional and request a blood test to check your kidney function.
Causes of high creatinine levels
While elevated creatinine can signal kidney disease, other factors may also contribute to higher-than-normal levels. These include:
- Dehydration – Reduced fluid intake can decrease kidney function and lead to a temporary rise in creatinine.
- High protein intake – Eating large amounts of red meat or protein supplements can affect creatinine levels.
- Intense exercise – Muscle breakdown during vigorous exercise can temporarily increase creatinine.
- Certain medications – Some antibiotics, blood pressure drugs or non-steroidal anti-inflammatory drugs (NSAIDs) may affect kidney function.
- Urinary tract blockage – Kidney stones or an enlarged prostate can interfere with urine flow, affecting filtration.
What happens if creatinine levels are too high?
Persistently high creatinine levels are usually investigated further through additional blood and urine tests, as well as imaging studies if needed. These tests help determine whether there is an underlying kidney problem and, if so, how advanced it may be.
If chronic kidney disease (CKD) is diagnosed, the condition is typically managed through lifestyle changes and medical treatment, including:
-
Controlling blood sugar – Managing diabetes can help prevent further kidney damage.
-
Lowering blood pressure – Keeping blood pressure within healthy ranges can protect kidney function.
-
Reducing salt and protein intake – A kidney-friendly diet may help reduce strain on your kidneys.
-
Staying well hydrated – Drinking enough fluids can help your kidneys flush out waste more effectively.
-
Avoiding nephrotoxic medications – Some drugs can harm the kidneys and may need to be adjusted or stopped under medical guidance.
Can high creatinine levels return to normal?
Yes, in some cases. If high creatinine levels are caused by a temporary issue such as dehydration, infection or medication side effects, levels can return to normal with appropriate treatment and care.
However, if high creatinine levels are due to chronic kidney disease, they may not return to previous levels, but progression of the disease can often be slowed with early diagnosis, lifestyle changes and regular monitoring.
Does creatinine affect kidney function?
Creatinine is one of the most widely used markers to assess kidney function. It offers a quick, inexpensive and non-invasive way to screen for potential kidney damage.
However, a single high result doesn’t always mean something is wrong - it’s the trend over time, alongside other indicators like eGFR and symptoms, that provides the clearest picture.
That’s why regular health checks, including kidney function tests, are so important, especially if you have risk factors such as diabetes, high blood pressure or a family history of kidney disease.
Get peace of mind with a private blood test from Bluecrest Wellness
At Bluecrest Wellness, we make it simple to take control of your kidney health. Our kidney function tests check essential biomarkers such as creatinine, urea and eGFR to give you clear insights into how well your kidneys are working.
Whether you choose one of our Health MOTs you’ll receive fast, accurate results from accredited labs - plus guidance on what your results mean and what to do next. With over 350 clinics across the UK and Ireland, it’s easy to book a test close to home.
