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• Symptoms
• Diagnosis and Tests
• Prevention and Risk Factors
• Treatments and Therapies

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Summary

If you have anemia, your blood does not carry enough oxygen to the rest of your body. The most common cause of anemia is not having enough iron. Your body needs iron to make hemoglobin. Hemoglobin is an iron-rich protein that gives the red color to blood. It carries oxygen from the lungs to the rest of the body.

Anemia has three main causes: blood loss, lack of red blood cell production, and high rates of red blood cell destruction.

Conditions that may lead to anemia include:

• Heavy periods
• Pregnancy
• Ulcers
• Colon polyps or colon cancer
• Inherited disorders
• A diet that does not have enough iron, folic acid or vitamin B12
• Blood disorders such as sickle cell anemia and thalassemia, or cancer
• Aplastic anemia, a condition that can be inherited or acquired
• G6PD deficiency, a metabolic disorder

Anemia can make you feel tired, cold, dizzy, and irritable. You may be short of breath or have a headache.

Your doctor will diagnose anemia with a physical exam and blood tests. Treatment depends on the kind of anemia you have.

NIH: National Heart, Lung, and Blood Institute

Start Here

• Anemia (American Academy of Family Physicians) Also in Spanish
• What Is Anemia? (National Heart, Lung, and Blood Institute) Also in Spanish
• Your Guide to Anemia (National Heart, Lung, and Blood Institute) - PDF

Symptoms

• Anemia Symptoms (National Heart, Lung, and Blood Institute)

Diagnosis and Tests

• Anemia Diagnosis (National Heart, Lung, and Blood Institute)
• Blood Smear (National Library of Medicine) Also in Spanish
• Blood Tests (National Heart, Lung, and Blood Institute) Also in Spanish
• Bone Marrow Test (National Library of Medicine) Also in Spanish
• Complete Blood Count (CBC) (National Library of Medicine) Also in Spanish
• Ferritin Blood Test (National Library of Medicine) Also in Spanish
• Haptoglobin (HP) Test (National Library of Medicine) Also in Spanish
• Hemoglobin Electrophoresis (National Library of Medicine) Also in Spanish
• Iron Tests (National Library of Medicine) Also in Spanish
• Lactate Dehydrogenase (LDH) Isoenzymes Test (National Library of Medicine) Also in Spanish
• Lactate Dehydrogenase (LDH) Test (National Library of Medicine) Also in Spanish
• Red Blood Cell (RBC) Indices (National Library of Medicine) Also in Spanish
• Reticulocyte Count (National Library of Medicine) Also in Spanish
• Vitamin B Test (National Library of Medicine) Also in Spanish

Prevention and Risk Factors

• Anemia Causes and Risk Factors (National Heart, Lung, and Blood Institute)

Treatments and Therapies

• Anemia Treatment and Management (National Heart, Lung, and Blood Institute)
• Iron (National Institutes of Health, Office of Dietary Supplements) Also in Spanish
• Treatments for Blood Disorders (National Heart, Lung, and Blood Institute) Also in Spanish
• Vitamin B12 (National Institutes of Health, Office of Dietary Supplements) Also in Spanish

Related Issues

• Anemia in Chronic Kidney Disease (National Institute of Diabetes and Digestive and Kidney Diseases) Also in Spanish
• Craving and Chewing Ice: A Sign of Anemia? (Mayo Foundation for Medical Education and Research) Also in Spanish
• Managing Anemia When You Have Cancer (American Cancer Society) Also in Spanish

Specifics

• Anemia Due to Excessive Bleeding (Merck & Co., Inc.) Also in Spanish
• Anemia of Inflammation or Chronic Disease (National Institute of Diabetes and Digestive and Kidney Diseases) Also in Spanish
• Hemoglobin C, S-C, and E Diseases (Merck & Co., Inc.) Also in Spanish
• Hemolytic Anemia (National Heart, Lung, and Blood Institute) Also in Spanish
• Iron-Deficiency Anemia (National Heart, Lung, and Blood Institute) Also in Spanish
• Paroxysmal Nocturnal Hemoglobinuria (PNH) (Aplastic Anemia and MDS International Foundation)
• Vitamin B12-Deficiency Anemia (National Heart, Lung, and Blood Institute) Also in Spanish
• Vitamin Deficiency Anemia (Mayo Foundation for Medical Education and Research) Also in Spanish

Genetics

• Congenital dyserythropoietic anemia: MedlinePlus Genetics (National Library of Medicine)
• Diamond-Blackfan anemia: MedlinePlus Genetics (National Library of Medicine)
• Ghosal hematodiaphyseal dysplasia: MedlinePlus Genetics (National Library of Medicine)
• Glucose phosphate isomerase deficiency: MedlinePlus Genetics (National Library of Medicine)
• Hereditary folate malabsorption: MedlinePlus Genetics (National Library of Medicine)
• Hereditary spherocytosis: MedlinePlus Genetics (National Library of Medicine)
• Hypochromic microcytic anemia with iron overload: MedlinePlus Genetics (National Library of Medicine)
• Imerslund-Gräsbeck syndrome: MedlinePlus Genetics (National Library of Medicine)
• Iron-refractory iron deficiency anemia: MedlinePlus Genetics (National Library of Medicine)
• Majeed syndrome: MedlinePlus Genetics (National Library of Medicine)
• Mucolipidosis type IV: MedlinePlus Genetics (National Library of Medicine)
• Paroxysmal nocturnal hemoglobinuria: MedlinePlus Genetics (National Library of Medicine)
• Phosphoglycerate kinase deficiency: MedlinePlus Genetics (National Library of Medicine)
• Pyruvate kinase deficiency: MedlinePlus Genetics (National Library of Medicine)
• Thiamine-responsive megaloblastic anemia syndrome: MedlinePlus Genetics (National Library of Medicine)
• TRNT1 deficiency: MedlinePlus Genetics (National Library of Medicine)
• X-linked sideroblastic anemia: MedlinePlus Genetics (National Library of Medicine)

Statistics and Research

• Anemia Prevalence: United States, August 2021-August 2023 (Centers for Disease Control and Prevention)
• FastStats: Anemia or Iron Deficiency (National Center for Health Statistics)

Clinical Trials

• ClinicalTrials.gov: Anemia, Iron-Deficiency (National Institutes of Health)

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

• Article: Long-term safety and effectiveness of roxadustat in Chinese patients with chronic...
• Article: Longitudinal Associations Between Maternal Anemia and Breastfeeding Practices on Infant Hemoglobin...
• Article: Long-Term Transfusion Independence with Luspatercept Versus Epoetin Alfa in Erythropoiesis-Stimulating Agent-Naive,...
• Anemia -- see more articles

Find an Expert

• National Heart, Lung, and Blood Institute
• National Institute of Diabetes and Digestive and Kidney Diseases

Children

• Anemia (Nemours Foundation)
• Anemia in the Newborn (Merck & Co., Inc.) Also in Spanish
• Diamond-Blackfan Anemia (For Parents) (Nemours Foundation) Also in Spanish
• Hereditary Spherocytosis (Nemours Foundation) Also in Spanish
• Iron-Deficiency Anemia (Nemours Foundation) Also in Spanish
• Pyruvate Kinase Deficiency (For Parents) (Nemours Foundation)
• What's Anemia? (For Kids) (Nemours Foundation) Also in Spanish

Teenagers

• Anemia (For Teens) (Nemours Foundation) Also in Spanish

Women

• Anemia and Pregnancy (American Society of Hematology)
• Iron-Deficiency Anemia (Department of Health and Human Services, Office on Women's Health) Also in Spanish

Older Adults

• Anemia (AGS Health in Aging Foundation)

Patient Handouts

• Anemia (Medical Encyclopedia) Also in Spanish
• Anemia caused by low iron - infants and toddlers (Medical Encyclopedia) Also in Spanish
• Anemia of chronic disease (Medical Encyclopedia) Also in Spanish
• Febrile (warm) and cold agglutinins (Medical Encyclopedia) Also in Spanish
• Ferritin blood test (Medical Encyclopedia) Also in Spanish
• Hemolytic anemia (Medical Encyclopedia) Also in Spanish
• Iron deficiency anemia (Medical Encyclopedia) Also in Spanish
• Pernicious anemia (Medical Encyclopedia) Also in Spanish
• Vitamin B12 deficiency anemia (Medical Encyclopedia) Also in Spanish
• Vitamin B12 level (Medical Encyclopedia) Also in Spanish