What this article covers
- What is creatinine and why do the kidneys clear it?
- What is eGFR and why does it matter more than creatinine?
- The five stages of chronic kidney disease
- Why creatinine rises temporarily in a hot climate
- The painkiller link: a risk many people do not know about
- The most common causes of raised creatinine in the region
- How to prepare for a kidney function test
- Symptoms that need urgent attention
- Questions to ask your doctor about your results
What is creatinine and why do the kidneys clear it?
Creatinine is a chemical waste product that your muscles produce naturally during daily activity. It is a byproduct of creatine, which muscles use to generate energy. Creatinine passes into the bloodstream and the kidneys filter it out into the urine.
Because the body produces creatinine at a fairly steady rate, its level in the blood reflects how well the kidneys are doing their job. When kidney efficiency falls, creatinine starts to accumulate and the blood level rises, which is what makes it a useful marker of kidney function.
Normal creatinine levels depend on muscle mass and differ between men and women and between people of different builds. A muscular man may have a creatinine at the high end of normal with perfectly healthy kidneys, while a slim woman may have a creatinine at the low end of normal. This is the main reason why eGFR matters more than the raw creatinine number on its own.
Approximate normal creatinine ranges
| Group | Normal range (mg/dL) | Note |
|---|---|---|
| Adult men | 0.7 – 1.3 | Depends on muscle mass |
| Adult women | 0.5 – 1.1 | Lower because of smaller muscle mass |
| Older adults | Slightly below adult range | Muscle mass decreases with age |
| Children | 0.3 – 0.7 | Varies with age and size |
What is eGFR and why does it matter more than creatinine?
The estimated Glomerular Filtration Rate (eGFR) is a calculated number that estimates how much blood your kidneys filter per minute. Laboratories calculate it automatically from your creatinine level together with your age and sex.
A normal eGFR is above 90 millilitres per minute per 1.73 square metres of body surface area. The value naturally falls a little with age even in healthy people, which is why your age is so important in interpreting the result.
A 2008 study published in the journal Renal Failure tested different eGFR formulas on healthy Arab adults and found that some equations developed in Western studies may not accurately reflect kidney function in Arab populations, where body build and muscle mass differ. This is one more reason why your result should always be interpreted by a doctor who knows your full picture.
Reading your eGFR result
Source: KDIGO 2024 Clinical Practice Guideline for CKD
The five stages of chronic kidney disease
Chronic Kidney Disease (CKD) is diagnosed when eGFR stays below 60 for three months or more, or when other signs of kidney damage such as protein in the urine are present. It is divided into five stages that help doctors plan treatment.
A 2023 review in the International Journal of Nephrology and Renovascular Disease concluded that CKD represents a growing burden across the Middle East and Africa, with significant gaps in early detection and limited access to dialysis services in some countries. The leading causes in the region are diabetes and high blood pressure.
The encouraging reality is that the early stages can be slowed substantially, or even stabilised, if the underlying cause is controlled. Later stages require careful planning with a kidney specialist to decide when dialysis or transplantation is needed.
Chronic kidney disease stages by eGFR
| Stage | eGFR value | Description | Typical monitoring |
|---|---|---|---|
| G1 | 90 or above | Normal with signs of damage | Yearly |
| G2 | 60 – 89 | Mildly reduced | Yearly |
| G3a | 45 – 59 | Mildly to moderately reduced | Every 6 months |
| G3b | 30 – 44 | Moderately to severely reduced | Every 3-4 months |
| G4 | 15 – 29 | Severely reduced | Every 3 months with nephrologist |
| G5 | Below 15 | Kidney failure | Dialysis or transplant planning |
Why creatinine rises temporarily in a hot climate
Dehydration from extreme heat or heavy exertion reduces the volume of blood reaching the kidneys temporarily, which lowers their efficiency at filtering creatinine without there being any actual kidney disease. This is called a pre-renal rise in creatinine and it reverses once fluid intake is restored.
In our region where summer temperatures regularly exceed 40 degrees Celsius, this temporary rise is common, particularly among outdoor and agricultural workers who spend long hours in the heat. If you have a high creatinine result and you were dehydrated or physically exhausted before the test, tell your doctor.
If your result is elevated for the first time, ask your doctor about repeating the test after a few days of adequate rest and good hydration before drawing conclusions. The difference between a transient dehydration effect and a genuine kidney problem is important and a single reading cannot answer it.
The painkiller link: a risk many people do not know about
Non-steroidal anti-inflammatory drugs (NSAIDs), which include ibuprofen, diclofenac and naproxen, are available without prescription in many countries in the region. They are effective for short-term pain but regular use carries a genuine risk to the kidneys.
A review published in the journal Advances in Therapy in 2023 confirmed that NSAIDs narrow the blood vessels supplying the kidneys and reduce renal blood flow. The risk is greatest in people who already have some reduction in kidney function, those with high blood pressure, and those taking diuretics.
If your eGFR is below normal or at the low end of the normal range, ask your doctor before taking any drug from this class. Paracetamol at the correct dose is generally safer for the kidneys as an alternative, though even paracetamol is harmful in overdose.
The most common causes of raised creatinine in the region
Diabetes and high blood pressure are the two most common causes of chronic kidney disease in the Middle East. A study published in BMJ Open in 2018 on people in the UAE found a strong association between type 2 diabetes and reduced kidney function, even in the early stages of the disease. Persistently high blood sugar damages the tiny blood vessels in the kidneys gradually over years.
Other causes include kidney inflammation (nephritis), recurrent kidney stones, certain medications taken at high doses such as some antibiotics and contrast agents used in scans, and inherited conditions such as polycystic kidney disease. Acute kidney injury is a different and often reversible situation where kidney function falls rapidly over hours or days after a major insult such as surgery, severe bleeding or poisoning by a drug.
Less commonly recognised but clinically relevant is the herbal remedy risk. Several preparations sold in markets across the region contain compounds with documented kidney toxicity, and patients often do not mention them to doctors because they consider them natural and safe. If you take any herbal preparation regularly, tell your doctor.
How to prepare for a kidney function test
Creatinine testing does not usually require fasting on its own, but it is often ordered as part of a broader panel that includes fasting glucose or a lipid profile. Check with the clinic or lab when you book to avoid making an unnecessary second trip. The most important preparation step is making sure you are well hydrated on the day and the evening before, because even mild dehydration produces a misleading result.
If you exercise heavily or do physically demanding work, mention this to your doctor because your normal creatinine may sit higher than the printed reference range without any kidney problem. A bodybuilder or a construction worker may have a creatinine that would alarm a doctor in a sedentary patient but is perfectly normal for their muscle mass. Also report every painkiller, supplement or herbal remedy you take regularly, as some affect the reading or conceal an underlying problem that needs attention.
In parts of the region where access to accredited laboratories is limited, try to use a lab that calibrates its equipment regularly, especially if you are monitoring a chronic condition over time. Results from different labs can vary enough to be misleading if their standards differ, and an apparent improvement or worsening may simply reflect a change in the lab rather than a change in your health. If you switch labs, try to do the test at the same time of day and under the same preparation conditions so the comparison holds.
Preparing for your kidney function test
- 1Drink enough water on the day and the day before the test
- 2Avoid heavy physical exercise for a full day before the test
- 3Tell your doctor about every medicine, painkiller or supplement you take
- 4Mention any recent exposure to extreme heat or severe dehydration
- 5Use an accredited laboratory for results that can be compared over time
Symptoms that need urgent attention
In the early stages of kidney disease there are usually no symptoms, which is why regular testing is important for anyone with diabetes, high blood pressure or a family history of kidney problems. The disease is frequently discovered by chance on a routine blood test rather than because the person felt unwell. This silent progression is one of the most dangerous features of CKD, because by the time symptoms appear, significant damage has often already occurred.
Go to a doctor promptly if you notice significant swelling of the ankles, feet or face alongside high blood pressure, a clear drop in urine output, severe unexplained tiredness that sleep does not explain, persistent nausea particularly in the morning, skin itching without a visible rash, a severe headache with raised blood pressure, or urine that has turned dark or contains visible blood. These symptoms may indicate that waste products are accumulating in the blood because the kidneys can no longer clear them efficiently.
Dialysis access is not uniformly available across the region and its cost is significant, with long waiting times in some countries. This makes prevention, early detection and slowing the progression of kidney disease far more valuable than treatment at the stage of failure. Controlling diabetes and blood pressure and avoiding regular anti-inflammatory painkiller use are the three most effective tools for keeping eGFR stable. Every measure that keeps it above 30 protects years of quality of life and delays or avoids the need for dialysis entirely.
Questions to ask your doctor about your results
Many patients receive kidney function results without understanding what each number means, and some feel too embarrassed to ask for an explanation. You are entitled to know what your result means and what the next step is. Start with a simple question: is this result normal for my age and my health situation?
If your eGFR is below normal, ask what may have caused the drop, whether it is falling over time or staying stable, whether you need additional tests such as a urine protein measurement or an ultrasound of the kidneys, and whether any medicines or habits should be changed to protect your kidney function.
If you have diabetes or high blood pressure and your kidneys are still functioning normally, the important question is how often you should repeat this test to make sure function is not quietly declining. Regular monitoring is not a sign of a problem. It is the only reliable way to catch any decline early, before it becomes difficult to manage.
The Sihtak app lets you log your creatinine and eGFR results with dates and track them over time. The AI assistant can explain what your numbers mean in the context of your wider health picture and remind you when a repeat test is due.
Frequently asked questions
Does a high creatinine always mean kidney disease?
Not always. Dehydration, intense physical exertion and a large muscle mass can all raise creatinine temporarily. A single high reading needs to be repeated and compared with eGFR and urine protein before drawing conclusions.
What is the difference between acute kidney injury and chronic kidney disease?
Acute kidney injury develops over hours or days and is often reversible when the cause is treated. Chronic kidney disease develops slowly over months or years and does not fully reverse, though its progression can be slowed significantly. An eGFR below 60 for three months or more points to chronic disease.
Is eGFR read differently in older people or slim people?
Yes. Muscle mass decreases with age and is lower in women and slim people, so their creatinine is lower but eGFR may not accurately reflect true kidney function. Your doctor takes this into account when interpreting results.
How often should I test my kidney function?
If you have diabetes, high blood pressure or a family history of kidney disease, at least once a year. With diagnosed CKD the doctor sets the frequency based on stage, and it may be every three months in higher stages.
Can I take ibuprofen if my kidneys are normal?
Occasional use in otherwise healthy people is generally acceptable. The problem is regular or long-term use, and in people with high blood pressure or existing kidney risk. If you need a painkiller regularly, discuss safer options with your doctor.
Does high blood pressure damage the kidneys, or do damaged kidneys raise blood pressure?
Both are true. High blood pressure damages the kidney's blood vessels, and poor kidney function raises blood pressure. This makes controlling blood pressure one of the most important tools for protecting the kidneys.
What does protein in the urine mean if my creatinine is normal?
Proteinuria is an early sign of kidney damage that can appear before creatinine rises or eGFR falls. If it is consistently present across several tests, it needs medical evaluation and monitoring even if other numbers look normal.
Sources
- Al-Khader AA, Tamim H, Sulaiman MH et al: What is the most appropriate formula to use in estimating glomerular filtration rate in adult Arabs without kidney disease?, Renal failure, 2008
- Osman WM, Jelinek HF, Tay GK et al: Clinical and genetic associations of renal function and diabetic kidney disease in the United Arab Emirates: a cross-sectional study, BMJ open, 2018
- Al-Ghamdi S, Abu-Alfa A, Alotaibi T et al: Chronic Kidney Disease Management in the Middle East and Africa: Concerns, Challenges, and Novel Approaches, International journal of nephrology and renovascular disease, 2023
- GBD 2023 Chronic Kidney Disease Collaborators: Global, regional, and national burden of chronic kidney disease in adults, 1990-2023, Lancet, 2025
- Baker M, Perazella MA: NSAIDs in CKD: Are They Safe?, American journal of kidney diseases, 2020
- LaForge JM, Urso K, Day JM et al: Non-steroidal Anti-inflammatory Drugs: Clinical Implications, Renal Impairment Risks, and AKI, Advances in therapy, 2023
This content is for health education only and is not a substitute for medical advice. If you have symptoms that worry you, see your doctor.