Stage 3 kidney disease is treated primarily by slowing its progression through blood pressure control, dietary changes, blood sugar management (if you have diabetes), and regular monitoring. There is no cure, but many people stay at stage 3 for years or even decades without progressing to kidney failure. The goal of treatment is protecting the kidney function you still have.
At stage 3, your kidneys filter waste at roughly 30 to 59 percent of normal capacity, measured by a blood test called eGFR (estimated glomerular filtration rate). Stage 3 is split into two substages: 3a, with an eGFR of 45 to 59, and 3b, with an eGFR of 30 to 44. The lower your number, the more function you’ve lost and the more aggressively treatment typically needs to be managed.
Blood Pressure Control
High blood pressure is both a cause and a consequence of kidney disease, and bringing it down is the single most impactful thing most people can do to protect remaining kidney function. Current guidelines generally target a systolic blood pressure (the top number) below 120 mmHg for people with CKD, though your doctor may adjust that target based on your age and other conditions.
A class of blood pressure medications called ACE inhibitors or ARBs is typically the first choice because these drugs reduce pressure inside the kidneys’ filtering units, not just in your blood vessels generally. This dual benefit slows kidney damage beyond what blood pressure reduction alone would accomplish. If you’re prescribed one of these, expect periodic blood tests to check your potassium levels, since these medications can cause potassium to rise.
Dietary Changes That Protect Your Kidneys
What you eat has a direct effect on how hard your kidneys have to work. The key dietary shifts at stage 3 involve protein, sodium, and sometimes potassium and phosphorus.
Protein
Reducing protein intake is one of the most evidence-backed dietary strategies for slowing progression to kidney failure. The Academy of Nutrition and Dietetics recommends people with stage 3 to 5 CKD eat 0.55 to 0.60 grams of protein per kilogram of body weight per day. For a 170-pound person, that works out to roughly 42 to 46 grams of protein daily, which is noticeably less than what most people eat. A single chicken breast contains about 30 grams, so you can see how quickly it adds up. Working with a renal dietitian makes this manageable without leaving you malnourished.
Sodium
General dietary guidelines cap sodium at 2,300 milligrams per day, but many people with CKD need to go lower. Sodium drives fluid retention and raises blood pressure, both of which strain damaged kidneys. Most excess sodium comes from processed and restaurant foods rather than the salt shaker, so reading nutrition labels and cooking more meals at home are the most effective changes.
Potassium and Phosphorus
Whether you need to restrict potassium and phosphorus depends on your blood work. At stage 3a, many people handle these minerals fine. At stage 3b, the kidneys start struggling to clear excess potassium and phosphorus, which can affect your heart rhythm and bone health respectively. There’s no single daily limit that applies to everyone. Your lab results will guide how tightly you need to manage these, and a dietitian can help you identify which foods to moderate.
Managing Diabetes Alongside CKD
If diabetes caused or contributes to your kidney disease, blood sugar control becomes a central part of treatment. The international kidney guidelines (KDIGO) recommend an individualized HbA1c target ranging from below 6.5% to below 8.0% for people with diabetes and CKD. That’s a wide range because the right target depends on your age, how long you’ve had diabetes, your risk of dangerous blood sugar drops, and how much kidney function remains.
A newer class of diabetes medications originally designed to lower blood sugar has shown significant kidney-protective benefits. These drugs, called SGLT2 inhibitors, work by helping your kidneys excrete excess sugar through urine, but they also reduce pressure inside the kidneys and lower inflammation. They’re now prescribed specifically for kidney protection in many CKD patients, even some without diabetes. For people with type 2 diabetes and CKD, another medication called finerenone has shown meaningful benefits. In a major trial with a median follow-up of 2.6 years, it reduced the risk of a combined outcome of kidney failure, significant kidney function decline, or kidney-related death by 18% compared to placebo. It also reduced cardiovascular events like heart attack, stroke, and heart failure hospitalization by 14%.
Exercise and Physical Activity
Stage 3 CKD is not a reason to stop exercising. In fact, staying active helps control blood pressure, blood sugar, and body weight, all of which directly affect kidney health. UK Kidney Association guidelines recommend people with non-dialysis CKD aim for 150 minutes of moderate-intensity aerobic activity per week, the same target as the general population. Walking briskly, cycling, and swimming all count.
On top of aerobic activity, strength and balance exercises on at least two days per week help preserve muscle mass, which matters because CKD can cause gradual muscle wasting over time. If you haven’t been active, the key is building up gradually rather than jumping into an intense routine. Even starting with 10-minute walks and adding a few minutes each week makes a real difference over months.
Medications to Avoid or Adjust
At stage 3, your kidneys clear medications more slowly, which means some common drugs can build up to harmful levels or cause further kidney damage. Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen and naproxen are the biggest everyday concern. They reduce blood flow to the kidneys and can accelerate damage, especially with regular use. Acetaminophen is generally the safer option for pain relief.
Certain heartburn medications (proton pump inhibitors), some antibiotics, and contrast dye used in CT scans can also pose risks. Before starting any new medication, including over-the-counter supplements and herbal products, make sure your prescriber knows your kidney function level. Many medications simply need a dose adjustment rather than being off-limits entirely.
Monitoring and What to Expect
At stage 3, your kidney function should be checked at least once a year through blood and urine tests. The two key numbers are your eGFR (measuring filtration capacity) and your urine albumin-to-creatinine ratio, or uACR (measuring protein leakage into your urine). Protein in the urine is one of the strongest predictors of whether kidney disease will progress. If your uACR is significantly elevated, expect testing at least twice a year.
Tracking these numbers over time matters more than any single result. A stable eGFR over two or three years is reassuring. A steady downward trend, even a slow one, signals that treatment needs to be intensified. Many people at stage 3a with well-controlled blood pressure and minimal protein in their urine never progress beyond that stage. People at stage 3b, or those with heavy proteinuria, diabetes, or uncontrolled blood pressure face higher risk and typically need closer follow-up.
The practical reality of living with stage 3 CKD is that treatment is mostly about consistent daily habits rather than dramatic medical interventions. Keeping blood pressure in range, eating less sodium and protein, staying physically active, and attending regular lab checks form the core of what slows this disease down. The earlier and more consistently you make these changes, the more kidney function you preserve long-term.