Last updated: February 06, 2026
Medically reviewed by: NKF Patient Education Team
Learn how anemia affects people with CKD, how it’s diagnosed and treated, and what questions to ask to feel better and protect your health.
About Anemia in CKD
Anemia means your blood does not have enough healthy red blood cells. Red blood cells carry oxygen throughout your body. When you have anemia, your body may not get the oxygen it needs to work well. This can make you feel tired and weak. It can also affect your heart and overall health. Chronic kidney disease (CKD) can increase your risk of having anemia, especially in later stages of the disease. Almost half of the people in the United States with stage 3a CKD have anemia. By stage 5 CKD (also known as kidney failure), more than 9 out of 10 people have anemia.
Everyone’s experience is different. Some people may have mild symptoms or no symptoms at first.
Causes
Anemia in CKD can happen for several reasons. These include:
- Low erythropoietin [eh-rith-roh-POY-uh-tin] (EPO): Healthy kidneys make a hormone called EPO that tells the body to make red blood cells. With CKD (especially kidney failure), the kidneys are less able to make EPO. This leads to your body making fewer red blood cells.
- Low iron: Iron is needed to make healthy red blood cells. People with CKD may lose iron (during dialysis) or not absorb enough iron from food.
- Low vitamin B12 or folate: Your body also needs these to make blood. If you don’t have enough, it can make it harder for your body to make healthy red blood cells.
- Chronic inflammation: People living with CKD often have inflammation (swelling throughout the body). Obesity, diabetes, and heart failure can also cause chronic inflammation. Inflammation can make it harder for your body to use iron properly.
- Blood loss: This can happen from frequent lab tests, dialysis, or stomach problems.
Anemia can have causes other than kidney disease, even in people living with CKD. Some examples include:
- Not eating enough iron-rich foods or trouble absorbing iron due to stomach or bowel problems
- Heavy blood loss from menstrual periods, ulcers, polyps, or hemorrhoids
- Long-term infections
- Cancer
- Autoimmune diseases, such as lupus, rheumatoid arthritis (RA), Hashimoto’s thyroiditis, Sjogren’s syndrome, Crohn’s disease, or ulcerative colitis (UC)
- Inherited (genetic) blood conditions like sickle cell disease or thalassemia that affect how red blood cells are made
Complications
If anemia is not treated, it can:
- Make fatigue (tiredness) and weakness worse
- Lower your quality of life, including how you feel physically, emotionally, and socially
- Increase strain on your heart
- Raise the risk of heart problems
- Make CKD symptoms harder to manage
Diagnosis
Anemia in CKD is diagnosed and treated based on your lab test results, your medical history, and any symptoms you may have.
Tests
Your healthcare team may use blood tests to check for anemia, such as:
- Hemoglobin (Hb): shows how much oxygen-carrying protein is in your blood. For people 15 years of age and older, anemia is usually defined as a Hb under 12 g/dL (for women) and under 13 g/dL (for men).
- Ferritin: shows how much iron is stored in your body. A ferritin level under 100 ng/mL in adults (under 200 ng/mL for adults on hemodialysis) suggests you may not have enough stored iron in your body.
- Transferrin: a protein that carries iron in your blood. Think of it like the number of “buses” you have to move iron around your body.
- Transferrin saturation (TSAT): shows how much iron each “bus” (transferrin) is carrying, or how full the buses are. A TSAT level under 20% suggests you may not have enough iron available in your blood.
These tests are used in combination to help guide treatment choices.
Treatment goals are not the same as levels for diagnosis, and they can be different for each person. Talk with your healthcare team about your target levels for hemoglobin (Hb), ferritin, and TSAT.
Treatment
Medications
Treatment depends on the cause of your anemia and how it affects your daily life. The first step is to treat the cause, such as low iron or vitamins. If medications are needed, these may include:
- Iron supplements: help raise your body’s available supply of iron to make red blood cells. They can be taken by mouth (tablets, capsules, or liquids) or through a vein (IV).
- Vitamins: your health care professional may recommend vitamin supplements, such as vitamin B12 (cobalamin) or folic acid, only if your body doesn’t have enough of these vitamins. Both are needed to make healthy red blood cells.
- EPO-stimulating medicines (also known as erythropoietin-stimulating agents or ESAs): help your body make more red blood cells by raising your body’s EPO levels. They are given as an injection under the skin (SubQ or SC) or given through a vein (IV) during dialysis. Examples include epoetin alfa (Epogen, Procrit, Retacrit), darbepoetin alfa (Aranesp), and methoxy polyethylene glycol-epoetin beta (Mircera). Because ESAs help your body make more red blood cells, your iron can be used up faster. So, most people taking an ESA will also need an iron supplement to make sure their body has enough.
- HIF-PH inhibitors: help your body make more of its own EPO and use iron better. These are tablets taken by mouth. Vadadustat (Vafseo) is the only version available in the United States, and only for people on dialysis.
- Blood transfusions: healthy red blood cells are given to you through a vein (IV). These are only used if anemia is severe or urgent. Healthcare professionals try to limit or avoid blood transfusions because they can lead to other health problems, including severe allergic reactions and iron overload. They can also make it harder to get a kidney transplant in the future.
Do not start any iron supplements or vitamins for anemia without talking to your care team first.
Nutrition
Nutrition is an important part of treating anemia. You may need to change what you eat to help manage anemia in CKD. A kidney dietitian can help you plan meals you enjoy while also protecting your kidneys.
If you have low levels of iron, vitamin B12, or folate, they may suggest foods like lean meats, beans, or fortified grains. Some of these foods can also be high in protein, sodium (salt), or phosphorus, so talk with your care team before making diet changes.
Preparing for your appointment
Questions to ask
- What is my hemoglobin level, and what is a healthy goal for me?
- Could any of my symptoms be caused by anemia?
- Do I have any other risk factors for anemia (in addition to my CKD)?
- What may be causing my anemia – low iron, low EPO, or something else?
- Do I need medicine to help raise my hemoglobin level?
- What side effects should I watch for with my anemia treatment?
- How often should my blood be checked to track my anemia?
- When should I reach out if my symptoms get worse or change?
