Generic Name: red blood cells
Other Names: RBCs
Drug Class: Blood Components
What are red blood cells, and what are they used for?
Red blood cells (RBCs), also known as erythrocytes, are cellular components of blood that give blood its characteristic red color.
Red blood cells contain hemoglobin, an iron-rich protein that carries oxygen from the lungs to all the tissues, and carbon dioxide back to the lungs to be eliminated in exhalation. Red blood cells are used for transfusion in patients who have insufficient tissue oxygen because of active bleeding or symptomatic anemia, to increase the red blood cell count, hemoglobin level, and consequently, blood’s oxygen carrying capacity.
Red blood cells, also known as packed red blood cells, used for transfusion are separated by centrifugal process from whole blood collected from donors and screened for infectious diseases. Red blood cells may also be collected directly from donors by apheresis, a process in which the donor’s blood is passed through a medical device that selectively removes red blood cells and the plasma and other components are infused back into the donor.
Red blood cells may undergo further processes such as washing, special filtering or irradiation to remove other blood components before transfusion in certain patients with special requirements. Red blood cells are matched for blood group (ABO) compatibility with the recipient before transfusion.
Warnings
- Do not use red blood cell transfusion to treat anemia that can be corrected with non-transfusion treatments such as iron therapy, unless immediate correction is required.
- Do not administer RBC transfusion to merely increase blood volume and/or oncotic pressure, improve wound healing or provide a sense of wellbeing.
- Monitor patients for signs of transfusion reaction, including vital signs, before, during, and after transfusion. If transfusion reaction is suspected, stop the transfusion, assess and stabilize the patient, and notify the blood bank to initiate an investigation.
- All RBC transfusions must be given using blood administration sets containing 170- to 260-micron filters or 20- to 40-micron microaggregate filters.
- RBC transfusion should be given through an exclusive venous port and no other medications or fluids other than normal saline should be simultaneously given through the same line without prior consultation with the medical director of the blood bank.
- Monitor for iron overload in patients chronically transfused with RBCs due to hemoglobinopathies such as sickle cell disease or thalassemia.
- RBC transfusions carry a risk for non-septic infections including human immunodeficiency virus (HIV) hepatitis B and C viruses (HBV and HCV), human T-lymphotropic virus (HTLV), cytomegalovirus (CMV), West Nile virus (WNV), parvovirus B19, Lyme disease, babesiosis, malaria, Chagas disease and variant Creutzfeldt-Jakob disease (vCJD).
- Consult with the blood bank medical director or a hematologist if you have questions regarding special transfusion requirements.

SLIDESHOW
Surprising Causes of Weight Gain See SlideshowWhat are the side effects of red blood cells?
Common side effects of red blood cells include:
- Hemolytic transfusion reactions that destroy red blood cells
- Feverish (febrile) non-hemolytic reactions
- Transfusion related acute lung injury (TRALI)
- Transfusion-associated circulatory overload (TACO)
- Allergic reactions such as:
- Hives (urticaria)
- Itching (pruritus)
- Wheezing
- Shortness of breath (dyspnea)
- Low blood pressure (hypotension)
- Serious allergic (anaphylactic) reactions including:
- Swelling under the skin and mucous membrane (angioedema)
- Respiratory distress
- Shock
- Transfusion-associated graft-versus-host disease (TA-GVHD)
- Transfusion-transmitted infections and septic reactions
- Post-transfusion bruising (purpura)
Call your doctor immediately if you experience any of the following symptoms or serious side effects while using this drug:
- Serious heart symptoms include fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness;
- Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
- Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out; or
- Serious eye symptoms include blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.
This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.
What are the dosages of red blood cells?
Insufficient Tissue Oxygen Delivery Due to Active Bleeding or Symptomatic Anemia
- 1 unit increase hemoglobin 1 g/dL in average-sized adults without active bleeding or hemolysis; usually given over 1-2 hours but not longer than 4 hours
- Rarely necessary to transfuse to hemoglobin over 10 g/dL
- Actively bleeding patients dosing and rate of administration varies depending on rate of bleeding and must be evaluated on a case-by-case basis
Pediatric:
- 10-15 mL/kg increases hemoglobin 2-3 g/dL in patients without active bleeding or hemolysis
- Actively bleeding patients dosing and rate of administration varies depending on rate of bleeding and must be evaluated on a case-by-case basis
Other Information
- Usually, blood loss over 20% of estimated total blood volume
What drugs interact with red blood cells?
Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.
- Red blood cells have no known severe, serious, moderate, or mild interactions with other drugs.
The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.
It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or health care provider if you have any questions about the medication.
Pregnancy and breastfeeding
- Cytomegalovirus-seronegative or CMV reduced risk (leukocyte reduced) red blood cells should be used in pregnant or breast-feeding women who are CMV-seronegative or whose CMV status is unknown.
Summary
Red blood cells (RBCs), also known as erythrocytes, are cellular components of blood that give blood its characteristic red color. Red blood cells are used for transfusion in patients who have insufficient tissue oxygen because of active bleeding or symptomatic anemia, to increase the red blood cell count, hemoglobin level, and consequently, blood’s oxygen carrying capacity. Common side effects of red blood cells include hemolytic transfusion reactions that destroy red blood cells, feverish (febrile) non-hemolytic reactions, transfusion related acute lung injury (TRALI), transfusion-associated circulatory overload (TACO), allergic reactions, transfusion-associated graft-versus-host disease (TA-GVHD), transfusion-transmitted infections and septic reactions, and post-transfusion bruising (purpura). Consult your doctor if pregnant or breastfeeding.
Multimedia: Slideshows, Images & Quizzes
-
Anemia: Common Causes, Symptoms, Types, and Treatment
Anemia is a disease marked by low numbers of red blood cells. Low iron deficiency or underlying disease, like cancer, may be to...
-
Picture of Twin-to-Twin Transfusion
Twin to twin transfusion syndrome (TTTS) occurs in identical twins or multiples when the blood vessels of the babies’ shared...
-
Picture of Pernicious Anemia
Pernicious anemia is a disease where large, immature, nucleated cells (megaloblasts, which are forerunners of red blood cells)...
-
What Foods Can I Eat to Increase My Hemoglobin?
What are the best foods for blood hemoglobin? Know about the foods that help increase the hemoglobin level in your blood. Learn...
-
Paroxysmal Nocturnal Hemoglobinuria: Tips for Taking Care of Yourself When You Have PNH
There are plenty of things you need to do to keep yourself healthy if you have Paroxysmal nocturnal hemoglobinuria (PNH). Learn...
Related Disease Conditions
-
Anemia
Anemia is the condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased. There are several types of anemia such as iron deficiency anemia (the most common type), sickle cell anemia, vitamin B12 anemia, pernicious anemia, and aplastic anemia. Symptoms of anemia may include fatigue, malaise, hair loss, palpitations, menstruation, and medications. Treatment for anemia includes treating the underlying cause for the condition. Iron supplements, vitamin B12 injections, and certain medications may also be necessary.
-
Bilirubin Test
Bilirubin is a waste product of the normal breakdown of red blood cells in the liver. Normal bilirubin levels vary from lab to lab, and range from around 0.2 to 1.2 mg/dL. High levels of bilirubin can be diagnosed with a bilirubin blood test. Causes of elevated levels of bilirubin in the blood can be caused by infections, viral hepatitis, anemia, genetic diseases, and liver problems. Symptoms of elevated bilirubin levels depend on the cause; however, jaundice is a common sign. Treatment for elevated bilirubin levels depend on the cause.
-
High Red Blood Cell Count (Polycythemia)
Polycythemia (elevated red blood cell count) is a rare blood disease in which the body produces too many red blood cells. Causes of polycythemia are either primary (acquired or genetic mutations) or secondary (diseases, conditions, high altitude).
-
How Do I Increase My Hemoglobin?
Low hemoglobin levels can be caused by anemia and low iron intake. Here are 9 ways to increase your hemoglobin through diet and supplements.
-
Can Doctors Tell if You Smoke From a Blood Test?
A nicotine test measures the level of nicotine or the chemicals cigarettes produce in the body. A lab examination called a nicotine test may help a doctor determine the nicotine content in a person's body.
-
What Does a Low or High MCHC Mean in a Blood Test?
High and low MCHC values are common conditions that affect many people. Learn the signs of high or low MCHC values, what causes them, how doctors diagnose them, and what you can do to treat them.
-
The Glycated Hemoglobin Test (HbA1c)
Second Source WebMD Medical Reference
-
Do All Cancers Show Up on Blood Tests?
Early diagnosis and treatment of cancer increase the chances of recovery and gives a better chance of survival. No single test can accurately diagnose cancer. An accurate diagnosis of cancer and the extent of its spread inside the body usually involves many tests. Blood tests are usually done in all cases of suspected cancer and may also be done routinely in healthy individuals. Not all cancers show up on blood tests. Blood tests can give information about the overall health status, such as thyroid, kidney and liver functions.
-
Pernicious Anemia
Pernicious anemia is a blood disorder in which the body does not make enough red blood cells due to a lack of vitamin B12 in the blood. Pernicious anemia can develop from a lack of a protein that helps the body absorb vitamin B12, not getting enough B12 in the diet, and certain intestinal conditions that interfere with the absorption of vitamin B12 such as Crohn's disease, celiac sprue, or ulcerative colitis. There is no cure for pernicious anemia, thus treatment is life-long.
-
Sickle Cell Disease (Anemia)
Sickle cell anemia (sickle cell disease), a blood disease that shortens life expectancy, is caused by inherited abnormal hemoglobin. Symptoms of sickle cell anemia may include bacterial infections, painful swelling of the hands and feet, fever, leg ulcers, fatigue, anemia, eye damage, and lung and heart injury. Treatment for sickle cell anemia aims to manage and prevent the worst manifestations of the disease and focuses on therapies that block red blood cells from stacking together, which can lead to tissue and organ damage and pain.
-
What Does It Mean When Your Hemoglobin Is Low?
What is considered low hemoglobin? What is anemia and what causes it? Learn the signs and treatments of low hemoglobin and anemia.
-
What Foods Are Good and Bad for Your Diet if You Have Anemia?
What is anemia? Learn foods that are good and bad for anemia.
-
What Causes Your Red Blood Cells to Be Low?
Any values considerably lower than the normal range are considered a low red blood cell (RBC) count. If your cell count is much lower than 4.2 million cells/mcL, then you may have anemia.
-
What Does It Mean When Your Hemoglobin A1C Is High?
Learn what it means when your hemoglobin A1C is high. Find out how A1C tests are used to diagnose diabetes and guide its treatment. See when a high A1C means something else.
-
What Is the Most Common Cause of Macrocytic Anemia?
The most common causes of macrocytic anemia include vitamin B12 deficiency and folate deficiency.
-
Can Cancer Be Detected by a Blood Test?
While blood tests can’t absolutely detect all cancers, certain blood tests can give your doctor an idea of how your organs are functioning and if they have been affected by cancer. No blood test can detect colon cancer. However, your doctor may order blood tests to get a picture of your overall health and use other screening methods to look for signs of colon cancer.
-
Can Liver Cancer Be Detected by a Blood Test?
Liver cancer is not detected by blood tests alone. Certain substances present in the blood called the blood markers may be elevated in patients with liver cancer. Raised levels of a tumor marker called alpha fetoprotein (AFP) can indicate diseases of the liver, including liver cancer.
-
What Is Hb H Disease?
Hemoglobin H (Hb H) disease is an inherited hemoglobin disorder in which three out of the four alpha-globin genes that are usually present are deleted or has a mutation that impairs alpha-globin chain production. This leads to an excess of beta-globin chains that are unstable, precipitate within the cell, and destroys the red blood cells. Hb H is a thalassemia-like syndrome defined by hemolysis and the production of ineffective red cells.
-
Anemia: How Is It Treated and Can It Be Cured?
How is anemia treated and can anemia be cured? Learn how to identify and manage anemia.
-
Paroxysmal Nocturnal Hemoglobinuria (PNH)
Paroxysmal nocturnal hemoglobinuria or PNH is a rare genetic disease in which there is an abnormal breakdown of red blood cells. Symptoms of PHN include irregular heartbeats, chest pain, abdominal pain, anemia, jaundice, seizures, and blood clots in the legs (DVTs). Treatment for PNH is directed toward the symptoms of the disease.
-
What Are the 3 Main Causes of Anemia?
Anemia is caused by three main factors: blood loss, low red blood cell production, and red blood cell destruction.
-
Can Blood Tests Detect Colon Cancer?
Colon cancer begins in the large intestine, which is the final part of the digestive tract. The functions of the intestine are reabsorbing fluids, processing waste products and eliminating solid waste from the body. Colon cancer is characterized by the development of malignant tumors arising in the inner wall of the colon or rectum. It usually begins as small, noncancerous (benign) clumps of cells called polyps that form on the inside of the colon. Over time these polyps can develop into colon cancers.
-
Do Blood Tests Show Pancreatic Cancer?
Blood tests are often used in combination with other clinical assessments and tests to diagnose pancreatic cancer.
-
Can Testicular Cancer Be Detected in Blood Tests?
The testicles lie in the scrotum at the base of the penis. They are responsible for the production of male sex hormones and sperms. Testicular cancer is the most common type of cancer occurring in American males between the ages of 15 to 35 years. Testicular cancer can be aggressive and spreading rapidly, but it is treatable.
-
Can Pancreatic Cancer Be Detected by Blood Test?
Currently, there is no blood test to confirm the diagnosis of pancreatic cancer. A doctor may suggest doing a blood tumor markers test for pancreatic cancer along with routine blood tests and radiological tests to confirm the diagnosis.
-
Can Lyme Disease Be Detected by a Blood Test?
Lyme disease can be detected by tests that look for antibodies in the blood. Learn more about Lyme disease testing, stages, and symptoms.
-
What Are Anemia Symptoms During Pregnancy?
Anemia during pregnancy is a common issue that affects many women. Learn the signs of anemia, what causes anemia, how doctors diagnose anemia, and what you can do to treat anemia in pregnancy.
-
Can Cancer Be Detected in Blood Tests?
When a person is suspected to have cancer, doctors may perform a variety of tests to help diagnose cancer. Different types of blood tests are done to check for abnormal cells, cancer cells, proteins, tumor markers or other substances made by the cancer cells. This helps determine if a person has cancer or any precancerous condition. Blood tests may also indicate if other organs of the body have been affected by cancer.
-
How Is Liver Cancer Usually Diagnosed?
The liver is the second largest organ (the first being the skin) in the human body. One blood test used to help diagnose liver cancer is the tumor marker alpha-fetoprotein (AFP), but it is not specific to liver cancer.
-
How Do You Fix Anemia?
Anemia describes a condition in which you have a low red blood cell count and low hemoglobin levels. This is a serious condition as red blood cells and hemoglobin carry oxygen to all your cells, allowing them to burn energy. If you’re anemic, you’ll likely feel fatigued and short of breath, lacking physical stamina. You may have heart problems and appear pale. Anemia is often a symptom of some other disease or condition, so treatment varies widely depending on the root cause.
-
How Does Anemia Affect Your Baby During Pregnancy?
Anemia occurs when you don't have enough red blood cells to transport adequate oxygen or iron. Anemia during pregnancy may contribute to early delivery or failure of the baby to grow to a healthy weight.
-
What Blood Tests Are Done in First Trimester of Pregnancy?
When you are pregnant, your doctor will do blood tests to check complete blood count, blood type, Rh factor, infections, birth defects, and more.
-
Can Prostate Cancer Be Detected by a Blood Test?
Prostate cancer develops in the prostate gland of men. It is one of the most common types of cancer. It is usually seen in men older than 50 years of age. The prostate is a small walnut-shaped gland that produces seminal fluid required to nourish and transports sperm. Prostate cancer develops slowly. More often, it is confined to the prostate gland, requiring minimal or no treatment.
-
How Does Anemia Affect Pregnancy?
Anemia is a condition in which your body doesn't make enough red blood cells. The most common type is iron-deficiency anemia which 50% of women develop during pregnancy.
-
What Is Macrocytic Anemia?
Macrocytic anemia is a condition in which red blood cells are larger than normal and hemoglobin levels in the blood are low due to increased RBC destruction.
-
How Do You Treat Anemia in Children?
What are anemia symptoms in children and how do you treat it?
-
Can a Blood Test Detect Ovarian Cancer?
A doctor may advise a blood test to patients having ovarian cancer. A cancer antigen-125 (CA-125) blood test is usually recommended to measure the levels of a protein called CA-125, which could be elevated in women who have ovarian cancer. This test is also used during the treatment of ovarian cancer because the level of this protein goes down as the tumor shrinks. This protein is elevated in more than 80 percent of women with advanced ovarian cancers and 50 percent of those with early-stage cancers.
-
What Is Diamond-Blackfan Anemia (DBA)?
Diamond-Blackfan anemia (DBA) is a rare blood disorder that affects the bone marrow. In this condition, the bone marrow fails to make red blood cells, which are essential for carrying oxygen from the lungs to all the other parts of the body. Blood cells are made in the bone marrow.
-
Is There a Blood Test for Ovarian Cancer?
The CA-125 blood test is one of clinical assessments used to diagnose ovarian cancer. However, CA-125 or other tumor markers alone are insufficient to diagnose ovarian cancer.
Treatment & Diagnosis
- Liver Blood Tests
- Creatinine Blood Test
- Hemoglobin: Normal, High, Low Levels, Age & Gender
- Ferritin Blood Test (Normal, High, Low, Levels)
- Complete Blood Count (CBC)
- Hemoglobin A1c Test
- CA 125 Ovarian Tumor Marker Blood Test
- Alpha-Fetoprotein Blood Test
- Is It OK to Smoke Before a Blood Test?
- Homocysteine (Normal and Elevated Levels Blood Test)
- Blood Transfusion
- Hemoglobin vs. Hematocrit
- What Does a Positive Occult Blood Test Indicate?
- Thyroid Blood Tests
- Fecal Occult Blood Test
- What Is an ALT Blood Test? Liver Function Test
- Acquired Methemoglobinemia
- Heart Attack - New Blood Test For Earlier Accurate Diagnosis
- Hepatitis C: What blood tests?
- West Nile: Halting West Nile By Transfusion
- Are Gout and Aplastic Anemia Related?
- Are Pernicious Anemia and Low Back Pain Related?
- Can Gout Cause Aplastic Anemia?
- What Is Hemoglobin A1c (HbA1c)?
- How Is Hemoglobin A1c (HbA1c) Measured?
- Why Is Hemoglobin A1c (HbA1c) Measured?
- Anemia During Pregnancy
Medications & Supplements
Subscribe to MedicineNet's General Health Newsletter
By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
https://www.rxlist.com/consumer_red_blood_cells_rbcs/drugs-condition.htm
https://reference.medscape.com/drug/rbcs-red-blood-cells-999507
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4001991/
https://www.utmb.edu/bloodbank/component-therapy/red-blood-cells
https://www.aabb.org/regulatory-and-advocacy/regulatory-affairs/regulatory-for-blood/whole-blood-and-red-blood-cell-components