eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m²: Is That High?

Written by

Ernestas K.

Clinical research writer specializing in human health, biology, and preventive medicine.

Reviewed against NKF, NIH, CDC, KDIGO, Mayo Clinic guidelines · Last reviewed March 26, 2026

Is eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m² Low, Normal, or High?

Finding out your eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m² can bring a wave of questions and concern. This number, significantly lower than what is typically observed, might be considered a very low eGFR. It suggests that your kidneys' filtering work is much less than usual. While this information can feel heavy, understanding what an eGFR of 18 mL/min/1.73m² means is a powerful first step towards navigating your health journey. Let's explore what this specific eGFR value might indicate for your overall wellness.

Hidden Risk of eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m²

An eGFR of 18 mL/min/1.73m² suggests a notable reduction in your kidney's filtering capacity. This level of kidney function can prompt concerns about the body's ability to clear waste and maintain balance. While the term "hidden risk" often applies to early stages, an eGFR at 18 mL/min/1.73m² signifies a more advanced state where the potential for broader health impacts becomes more pronounced. It's a point where the body's intricate systems might feel the strain of impaired kidney performance. The kidneys play a crucial role beyond just filtering, influencing blood pressure, red blood cell production, and bone health, as highlighted by organizations like the National Kidney Foundation. When the eGFR is 18 mL/min/1.73m², the efficient management of these vital functions could be challenged, which can affect one's energy levels and overall sense of well-being. Understanding this specific eGFR level can empower you to engage more deeply with healthcare professionals about comprehensive management strategies. The potential implications of such a low eGFR include:

• Challenges in maintaining a healthy balance of fluids and electrolytes, which are essential for many bodily processes.
• Increased buildup of waste products in the body, which might contribute to feelings of fatigue or nausea.
• Potential effects on bone health and red blood cell production due to reduced hormone regulation by the kidneys.
• A heightened need to carefully manage blood pressure, as the kidneys play a key role in its regulation.

What Does a eGFR (Estimated Glomerular Filtration Rate) Level of 18 mL/min/1.73m² Mean?

When we talk about your eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m², we are looking at a measurement that tells us how well your kidneys are filtering waste from your blood. Imagine your kidneys as two sophisticated water filters working constantly to keep your body clean and balanced. A healthy eGFR would be like those filters working at full power, effortlessly cleaning a large volume of water. However, an eGFR of 18 mL/min/1.73m² suggests that these filters are significantly slowed down, perhaps like trying to filter a large swimming pool with a very small, somewhat clogged kitchen sieve. This specific value means that the tiny filtering units within your kidneys, called glomeruli, are letting much less blood pass through each minute for cleaning. The number 18 mL/min/1.73m² is a direct indicator of this reduced cleaning power. It's not just a number on a lab report; it represents a tangible decrease in your kidney's ability to perform its essential tasks. This includes removing excess fluids, salts, and waste products that accumulate in the body. When your kidney function is at this level, it becomes more challenging for your body to maintain its internal balance, which can affect how you feel day-to-day. Understanding this helps explain why managing your health with an eGFR of 18 mL/min/1.73m² might involve careful attention to various aspects of your lifestyle and health routine. This eGFR reflects a stage where the kidneys are working much harder than they should, or not effectively enough, to keep you healthy, making a clear understanding of its meaning even more vital for your peace of mind and proactive health choices.

Lifestyle Changes for eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m²

Making thoughtful lifestyle choices, beyond just what you eat, can play a significant role when you have an eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m². These changes are not about reversing the number, but about supporting your overall well-being and helping your body manage its functions more effectively. Prioritizing regular physical activity, for instance, can enhance your energy levels and help manage blood pressure, which is often linked to kidney health. Even gentle exercises, as recommended by organizations like the American Heart Association, can contribute positively to your general health without overtaxing your system. Managing stress is another crucial area; chronic stress can have widespread effects on the body, so finding healthy outlets like meditation, hobbies, or spending time in nature can be beneficial for your mental and physical health. Ensuring you get adequate, restorative sleep each night also supports your body's repair processes and overall resilience. For someone with an eGFR of 18 mL/min/1.73m², avoiding certain habits, such as smoking, is especially important, as smoking can further affect blood vessel health and, by extension, kidney function. Limiting alcohol intake is also generally advised for overall health, particularly when kidneys are working at a reduced capacity. These lifestyle adjustments are about empowering yourself to create an environment where your body can function as optimally as possible, even with a significantly reduced eGFR, and fostering a sense of control over your health journey.

Diet Changes for eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m²

When your eGFR (Estimated Glomerular Filtration Rate) is 18 mL/min/1.73m², dietary choices become a very important part of your health management. Your kidneys are less able to filter and remove certain substances, so adjusting your diet can help reduce the burden on them. This isn't about giving up everything you enjoy, but about making informed choices that support your body. The goal is often to balance nutrients and minerals that might accumulate with a lower eGFR, while still getting all the nourishment you need. Organizations like the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) provide insights into dietary considerations for kidney health. With an eGFR of 18 mL/min/1.73m², a registered dietitian specializing in kidney health can be an invaluable resource to help tailor a personalized eating plan. They can guide you through the specific aspects of a kidney-friendly diet that are most relevant to your individual needs. This customized approach ensures you're getting proper nutrition while minimizing stress on your kidneys. Some general dietary adjustments that may be discussed when dealing with an eGFR of 18 mL/min/1.73m² include:

• Careful management of sodium intake to help control blood pressure and fluid balance, often by reducing processed foods and limiting added salt.
• Monitoring protein consumption, as your body breaks down protein into waste products that kidneys filter; the right amount is key, not too much or too little.
• Paying attention to potassium levels, found in many fruits and vegetables, as high levels can be a concern when kidney function is reduced.
• Considering phosphorus in your diet, found in dairy, nuts, and certain processed foods, as elevated levels can affect bone health with a low eGFR.

eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m² in Men, Women, Elderly, and Kids

The eGFR (Estimated Glomerular Filtration Rate) calculation takes into account factors like age, sex, and ethnicity, aiming to provide a more accurate picture of kidney function for individuals. However, an eGFR of 18 mL/min/1.73m² is a significantly low number regardless of these individual characteristics. While a slightly lower eGFR might be considered part of normal aging for some, a value of 18 mL/min/1.73m² is universally recognized as indicating notably reduced kidney function across all adult populations, including men and women. For elderly individuals, while their baseline eGFR might naturally be a bit lower than younger adults, an eGFR of 18 mL/min/1.73m² still represents a substantial decrease in kidney's cleaning capacity, often requiring careful management due to potential co-existing health conditions. In younger adults, including men and women, an eGFR this low is even more unexpected and typically points to a more pronounced underlying issue affecting kidney health. It's important to remember that these demographic factors are part of the initial calculation, but they don't lessen the importance of a specific eGFR result like 18 mL/min/1.73m². For children, the interpretation of eGFR values uses different formulas and ranges tailored to their unique growth and development, but similarly, a significantly low value would always be a serious finding indicating impaired kidney function. The critical point is that an eGFR of 18 mL/min/1.73m² demands attention and understanding for anyone, highlighting the kidney's reduced ability to filter and maintain the body's balance, irrespective of age or sex.

Medicine Effects on eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m²

Understanding how medications can interact with your body when your eGFR (Estimated Glomerular Filtration Rate) is 18 mL/min/1.73m² is a key part of your health journey. Many medications are processed and removed from the body by the kidneys. When your kidney's cleaning ability is significantly reduced, as indicated by an eGFR of 18 mL/min/1.73m², certain medicines might stay in your system longer than usual, potentially leading to higher levels and an increased risk of side effects. Conversely, some medications might not be as effective because they rely on healthy kidney function to be activated or reach their target effectively. This is why a thorough review of all your medications, including over-the-counter drugs, supplements, and herbal remedies, is so vital. Your healthcare team, including doctors and pharmacists, can assess whether any adjustments are needed for your specific eGFR and health profile. Organizations like the Mayo Clinic emphasize the importance of medication management in individuals with reduced kidney function. It's about finding the right balance to treat other conditions while protecting your kidneys. Being proactive and open with your healthcare provider about all substances you're taking ensures your treatment plan is safe and effective for your current eGFR. Key considerations for medications when your eGFR is 18 mL/min/1.73m² include:

• Adjusting the dosage of certain medications to prevent accumulation and potential toxicity, ensuring they are cleared appropriately.
• Carefully evaluating new medications to ensure they are kidney-friendly and won't put additional strain on your reduced kidney function.
• Monitoring for side effects more closely, as your body's ability to process and eliminate drugs may be altered.
• Avoiding certain medications that are known to be harmful to the kidneys or are not recommended at this specific eGFR level.

When to Retest eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m²

When your eGFR (Estimated Glomerular Filtration Rate) is found to be 18 mL/min/1.73m², repeating the test is often a crucial next step in understanding your kidney health. This isn't just about confirming a single result, but about seeing the bigger picture over time. A repeat eGFR measurement helps healthcare professionals assess if the value is stable, improving, or decreasing further. It provides valuable context to the initial finding. For a significantly low eGFR of 18 mL/min/1.73m², timely follow-up is particularly important. The frequency of repeat tests can vary based on individual circumstances and the advice of your healthcare team, but it is typically more regular than for someone with a normal eGFR. For example, the Kidney Disease: Improving Global Outcomes (KDIGO) organization often recommends more frequent monitoring for lower eGFR values to track trends and inform treatment decisions. These repeated tests also help to evaluate the effectiveness of any lifestyle adjustments or treatments that may have been started. It gives you and your care team a chance to observe how your kidneys are functioning under current conditions and to make informed decisions about future care. The process of retesting is a key part of a comprehensive approach to managing kidney health, offering reassurance and guidance as you navigate your health journey with an eGFR of 18 mL/min/1.73m².

eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m² — Frequently Asked Questions

When to See a Doctor About eGFR (Estimated Glomerular Filtration Rate) 18 mL/min/1.73m²

Discovering an eGFR (Estimated Glomerular Filtration Rate) of 18 mL/min/1.73m² often brings feelings of urgency and a need for clear guidance. It is important to know that this specific number warrants prompt discussion with a healthcare professional. This is not a moment for alarm, but rather a signal to engage actively with your medical team to understand what this eGFR means for you personally. They can help interpret this result within the context of your overall health, medical history, and any other symptoms you might be experiencing. Your doctor can discuss further diagnostic steps, such as additional tests, to pinpoint the underlying reasons for this specific eGFR reading and assess your overall kidney health. They will also be able to outline a tailored management plan, which might involve a combination of lifestyle adjustments, medication review, and specialized care. Proactively seeking this professional guidance empowers you to take charge of your health journey, ensuring you receive the most appropriate support and care for an eGFR of 18 mL/min/1.73m².