BACK TOTOP Browse A-ZSearchBrowse A-ZABCDEFGHIJKLMNOPQRSTUVWXYZ0-9 E-mail FormEmail ResultsName:Email address:Recipients Name:Recipients address:Message: Print-FriendlyBookmarksbookmarks-menuRBC countErythrocyte count; Red blood cell count; Anemia - RBC countAn RBC count is a blood test that measures how many red blood cells (RBCs) you have.RBCs contain hemoglobin, a protein which carries oxygen. How much oxygen your body tissues get depends on how many RBCs you have and how well they work.HemoglobinHemoglobin is a protein in red blood cells that carries oxygen. The hemoglobin test measures how much hemoglobin is in your blood.ImageRead Article Now Book Mark Article No audio descriptionWith audio descriptionRelated video goes here for no-HTML5 browsersRelated video goes here for no-HTML5 browsers How the Test is Performed A blood sample is needed.Blood sampleVenipuncture is the collection of blood from a vein. It is most often done for laboratory testing.ImageRead Article Now Book Mark Article How to Prepare for the Test No special preparation is necessary. How the Test will Feel When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away. Why the Test is Performed The RBC count is almost always part of a complete blood count (CBC) test.CBCA complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...ImageRead Article Now Book Mark Article The test can help diagnose different kinds of anemia (low number of RBCs) and other conditions affecting red blood cells.AnemiaAnemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. Different type...ImageRead Article Now Book Mark Article Other conditions that may require an RBC count are:Bone marrow disorder in which the marrow is replaced by scar tissue (myelofibrosis) Disease that damages kidney blood vessels (Alport syndrome) Alport syndromeAlport syndrome is a rare inherited disorder that damages the tiny blood vessels in the kidneys. It can also cause hearing loss and eye problems....ImageRead Article Now Book Mark Article Disorder in which red blood cells break down earlier than normal (hemolysis or paroxysmal nocturnal hemoglobinuria) Paroxysmal nocturnal hemoglobinuriaParoxysmal nocturnal hemoglobinuria is a rare disease in which red blood cells break down earlier than normal.ImageRead Article Now Book Mark Article White blood cell cancer (Waldenström macroglobulinemia)Waldenström macroglobulinemiaWaldenström macroglobulinemia (WM) is a cancer of the B lymphocytes (a type of white blood cell). WM is associated with the overproduction of protei...ImageRead Article Now Book Mark Article Normal Results Normal RBC ranges are:Male: 4.7 to 6.1 million cells per microliter (cells/mcL) Female: 4.2 to 5.4 million cells/mcLThe ranges above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your health care provider about the meaning of your specific test results. What Abnormal Results Mean Higher than normal numbers of RBCs may be due to:Bone marrow disease that causes abnormal increase in RBCs (polycythemia vera) Polycythemia veraPolycythemia vera (PV) is a bone marrow disease that leads to an abnormal increase in the number of blood cells. The red blood cells are the most af...Read Article Now Book Mark Article Cigarette smoking Dehydration (for example, from severe diarrhea) DehydrationDehydration occurs when your body does not have as much water and fluids as it needs. Dehydration can be mild, moderate, or severe, based on how much...ImageRead Article Now Book Mark Article Failure of the right side of the heart (cor pulmonale) Cor pulmonaleCor pulmonale is a condition that causes the right side of the heart to fail. Long-term high blood pressure in the arteries of the lung and right ve...ImageRead Article Now Book Mark Article Kidney tumor (renal cell carcinoma) Low blood oxygen level (hypoxia) Problem with heart's structure and function that is present at birth (congenital heart disease) Congenital heart diseaseCongenital heart disease (CHD) is a problem with the heart's structure and function that is present at birth.ImageRead Article Now Book Mark Article Scarring or thickening of the lungs (pulmonary fibrosis)Pulmonary fibrosisIdiopathic pulmonary fibrosis (IPF) is scarring or thickening of the lungs without a known cause.ImageRead Article Now Book Mark Article Your RBC count will increase for several weeks when you are in a higher altitude.Drugs that can increase the RBC count include:Anabolic steroids Erythropoietin Gentamicin TestosteroneLower-than-normal numbers of RBCs may be due to: Anemia Bleeding Bone marrow cancer called multiple myeloma Multiple myelomaMultiple myeloma is a blood cancer that starts in the plasma cells in the bone marrow. Bone marrow is the soft, spongy tissue found inside most bone...ImageRead Article Now Book Mark Article Bone marrow failure (for example, from radiation, toxins, or tumor) Deficiency of a hormone called erythropoietin (caused by kidney disease) Leukemia Malnutrition Pregnancy RBC destruction (hemolysis) due to transfusion, blood vessel injury, or other cause HemolysisHemolysis is the breakdown of red blood cells.Read Article Now Book Mark Article Too little iron, copper, folic acid, vitamin B6, or vitamin B12 in the diet CopperCopper is an essential trace element present in all body tissues. A small amount is needed for the body to function, but the body cannot make its ow...Read Article Now Book Mark Article Vitamin B6Vitamin B6 is a water-soluble vitamin. Water-soluble vitamins dissolve in water so the body cannot store them. Leftover amounts of the vitamin leav...ImageRead Article Now Book Mark Article Vitamin B12Vitamin B12 is a water-soluble vitamin. Water-soluble vitamins dissolve in water. After the body uses these vitamins, leftover amounts leave the bo...ImageRead Article Now Book Mark Article Too much water in the body (overhydration)Drugs that can decrease the RBC count include:Chemotherapy drugs Chloramphenicol and certain other antibiotics Hydantoins Methyldopa Nonsteroidal anti-inflammatory drugs (NSAIDs) Quinidine Risks There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.Other risks associated with having blood drawn are slight, but may include:Excessive bleeding Fainting or feeling lightheaded Multiple punctures to locate veins Hematoma (blood buildup under the skin) Infection (a slight risk any time the skin is broken) Open ReferencesReferencesGallagher PG. Hemolytic anemias: red blood cell membrane and metabolic defects. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 152.Little M. Anaemia. In: Cameron P, Little M, Mitra B, Deasy C, eds. Textbook of Adult Emergency Medicine. 5th ed. Philadelphia, PA: Elsevier; 2020:chap 13.Pincus MR, Abraham NZ, Bluth M. Interpreting laboratory results. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 9.Means RT. Approach to the anemias. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 149.AllVideoImagesTogBlood test - illustration Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. Preparation may vary depending on the specific test.Blood testillustrationFormed elements of blood - illustration Blood transports oxygen and nutrients to body tissues and returns waste and carbon dioxide. Blood distributes nearly everything that is carried from one area in the body to another place within the body. For example, blood transports hormones from endocrine organs to their target organs and tissues. Blood helps maintain body temperature and normal pH levels in body tissues. The protective functions of blood include clot formation and the prevention of infection.Formed elements of bloodillustrationBlood test - illustration Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. Preparation may vary depending on the specific test.Blood testillustrationFormed elements of blood - illustration Blood transports oxygen and nutrients to body tissues and returns waste and carbon dioxide. Blood distributes nearly everything that is carried from one area in the body to another place within the body. For example, blood transports hormones from endocrine organs to their target organs and tissues. Blood helps maintain body temperature and normal pH levels in body tissues. The protective functions of blood include clot formation and the prevention of infection.Formed elements of bloodillustration Tests for RBC count RBC countCBC blood testRBC indicesRelated Information CBC blood test(Medical Test)Hemoglobin(Medical Test)Peripheral(Special Topic)Splenomegaly(Symptoms)Cor pulmonale(Condition)Idiopathic pulmonary fibrosis(Condition)Polycythemia vera(Condition)Dehydration(Condition)Erythropoietin test(Medical Test)Anemia(Condition)Heart failure - InDepth(In-Depth)Anemia - InDepth(In-Depth)Vitamins and Phytonutrients - InDepth(In-Depth) Review Date: 1/9/2022 Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited. © 1997- All rights reserved. A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.Content is best viewed in IE9 or above, Firefox and Google Chrome browser.
RBC countErythrocyte count; Red blood cell count; Anemia - RBC countAn RBC count is a blood test that measures how many red blood cells (RBCs) you have.RBCs contain hemoglobin, a protein which carries oxygen. How much oxygen your body tissues get depends on how many RBCs you have and how well they work.HemoglobinHemoglobin is a protein in red blood cells that carries oxygen. The hemoglobin test measures how much hemoglobin is in your blood.ImageRead Article Now Book Mark Article No audio descriptionWith audio descriptionRelated video goes here for no-HTML5 browsersRelated video goes here for no-HTML5 browsers How the Test is Performed A blood sample is needed.Blood sampleVenipuncture is the collection of blood from a vein. It is most often done for laboratory testing.ImageRead Article Now Book Mark Article How to Prepare for the Test No special preparation is necessary. How the Test will Feel When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away. Why the Test is Performed The RBC count is almost always part of a complete blood count (CBC) test.CBCA complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...ImageRead Article Now Book Mark Article The test can help diagnose different kinds of anemia (low number of RBCs) and other conditions affecting red blood cells.AnemiaAnemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. Different type...ImageRead Article Now Book Mark Article Other conditions that may require an RBC count are:Bone marrow disorder in which the marrow is replaced by scar tissue (myelofibrosis) Disease that damages kidney blood vessels (Alport syndrome) Alport syndromeAlport syndrome is a rare inherited disorder that damages the tiny blood vessels in the kidneys. It can also cause hearing loss and eye problems....ImageRead Article Now Book Mark Article Disorder in which red blood cells break down earlier than normal (hemolysis or paroxysmal nocturnal hemoglobinuria) Paroxysmal nocturnal hemoglobinuriaParoxysmal nocturnal hemoglobinuria is a rare disease in which red blood cells break down earlier than normal.ImageRead Article Now Book Mark Article White blood cell cancer (Waldenström macroglobulinemia)Waldenström macroglobulinemiaWaldenström macroglobulinemia (WM) is a cancer of the B lymphocytes (a type of white blood cell). WM is associated with the overproduction of protei...ImageRead Article Now Book Mark Article Normal Results Normal RBC ranges are:Male: 4.7 to 6.1 million cells per microliter (cells/mcL) Female: 4.2 to 5.4 million cells/mcLThe ranges above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your health care provider about the meaning of your specific test results. What Abnormal Results Mean Higher than normal numbers of RBCs may be due to:Bone marrow disease that causes abnormal increase in RBCs (polycythemia vera) Polycythemia veraPolycythemia vera (PV) is a bone marrow disease that leads to an abnormal increase in the number of blood cells. The red blood cells are the most af...Read Article Now Book Mark Article Cigarette smoking Dehydration (for example, from severe diarrhea) DehydrationDehydration occurs when your body does not have as much water and fluids as it needs. Dehydration can be mild, moderate, or severe, based on how much...ImageRead Article Now Book Mark Article Failure of the right side of the heart (cor pulmonale) Cor pulmonaleCor pulmonale is a condition that causes the right side of the heart to fail. Long-term high blood pressure in the arteries of the lung and right ve...ImageRead Article Now Book Mark Article Kidney tumor (renal cell carcinoma) Low blood oxygen level (hypoxia) Problem with heart's structure and function that is present at birth (congenital heart disease) Congenital heart diseaseCongenital heart disease (CHD) is a problem with the heart's structure and function that is present at birth.ImageRead Article Now Book Mark Article Scarring or thickening of the lungs (pulmonary fibrosis)Pulmonary fibrosisIdiopathic pulmonary fibrosis (IPF) is scarring or thickening of the lungs without a known cause.ImageRead Article Now Book Mark Article Your RBC count will increase for several weeks when you are in a higher altitude.Drugs that can increase the RBC count include:Anabolic steroids Erythropoietin Gentamicin TestosteroneLower-than-normal numbers of RBCs may be due to: Anemia Bleeding Bone marrow cancer called multiple myeloma Multiple myelomaMultiple myeloma is a blood cancer that starts in the plasma cells in the bone marrow. Bone marrow is the soft, spongy tissue found inside most bone...ImageRead Article Now Book Mark Article Bone marrow failure (for example, from radiation, toxins, or tumor) Deficiency of a hormone called erythropoietin (caused by kidney disease) Leukemia Malnutrition Pregnancy RBC destruction (hemolysis) due to transfusion, blood vessel injury, or other cause HemolysisHemolysis is the breakdown of red blood cells.Read Article Now Book Mark Article Too little iron, copper, folic acid, vitamin B6, or vitamin B12 in the diet CopperCopper is an essential trace element present in all body tissues. A small amount is needed for the body to function, but the body cannot make its ow...Read Article Now Book Mark Article Vitamin B6Vitamin B6 is a water-soluble vitamin. Water-soluble vitamins dissolve in water so the body cannot store them. Leftover amounts of the vitamin leav...ImageRead Article Now Book Mark Article Vitamin B12Vitamin B12 is a water-soluble vitamin. Water-soluble vitamins dissolve in water. After the body uses these vitamins, leftover amounts leave the bo...ImageRead Article Now Book Mark Article Too much water in the body (overhydration)Drugs that can decrease the RBC count include:Chemotherapy drugs Chloramphenicol and certain other antibiotics Hydantoins Methyldopa Nonsteroidal anti-inflammatory drugs (NSAIDs) Quinidine Risks There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.Other risks associated with having blood drawn are slight, but may include:Excessive bleeding Fainting or feeling lightheaded Multiple punctures to locate veins Hematoma (blood buildup under the skin) Infection (a slight risk any time the skin is broken) Open ReferencesReferencesGallagher PG. Hemolytic anemias: red blood cell membrane and metabolic defects. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 152.Little M. Anaemia. In: Cameron P, Little M, Mitra B, Deasy C, eds. Textbook of Adult Emergency Medicine. 5th ed. Philadelphia, PA: Elsevier; 2020:chap 13.Pincus MR, Abraham NZ, Bluth M. Interpreting laboratory results. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 9.Means RT. Approach to the anemias. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 149.