Fatigue, Headache, Shortness of breath: 24 Possible Causes
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What causes fatigue, headache and shortness of breath? 24 possible conditions

See a list of possible causes in order from the most common to the least.


Cold and Flu Overview

Common colds and influenza are contagious infections that affect the respiratory system. Both are airborne illnesses, spread through coughing and sneezing. Shared symptoms include headache, cough, sore throat, and more.

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Learn more about anxiety with this overview of anxiety disorders.

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Pneumonia is an infection of the lungs caused by fungi, bacteria, or viruses. General symptoms include chest pain, fever, cough, and difficulty breathing.

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Generalized Anxiety Disorder

People who suffer from generalized anxiety disorder, or GAD, worry uncontrollably about common occurrences and situations. The condition may also be called chronic anxiety neurosis.GAD is different than normal feeling...

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High Blood Pressure Overview

High blood pressure (hypertension) increases your risk for heart attack, stroke, coronary heart disease, and other serious health problems.

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Infectious Mononucleosis

Infectious mononucleosis, or mono, refers to a group of symptoms usually caused by the Epstein-Barr virus (EBV).

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Iron Deficiency Anemia

Iron-deficiency anemia is the most common type of anemia, which occurs when the body does not have enough of the mineral iron. The body needs iron to produce hemoglobin.

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Chronic Bronchitis

Learn about the causes and treatment of acute bronchitis.

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Tuberculosis (TB) is a highly infectious disease that primarily affects the lungs. Read more on whom it affects and how to treat it.

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Diabetic Ketoacidosis

This condition is considered a medical emergency. Urgent care may be required.

Diabetic ketoacidosis (DKA) is a serious complication that stems from diabetes. If you don't have enough insulin to help your body process sugars (glucose), your body will start burning fat to fuel itself. As a result...

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Chemical Burns

This condition is considered a medical emergency. Urgent care may be required.

Find information about chemical burns and how to prevent them. Learn about the causes, symptoms, and treatment of chemical burns.

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What You Need to Know About Paroxysmal Nocturnal Hemoglobinuria

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disorder that causes red blood cells to break down sooner than they should.

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Learn about sarcoidosis and its causes, symptoms, diagnosis, treatment, and potential complications.

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Hypovolemic Shock

This condition is considered a medical emergency. Urgent care may be required.

Hypovolemic shock (hemorrhagic shock) is a life-threatening condition that results when you lose more than 20 percent of your body's blood or fluid supply, preventing the heart from pumping sufficient blood to your body.

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Parrot Fever (Psittacosis)

Parrot fever is an infection caused by a specific type of bacteria called Chlamydia psittaci. In most cases, humans catch parrot fever from birds, including parrots, chickens, turkeys, pigeons, cockatiels, parakeets...

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Acute Mountain Sickness

Acute mountain sickness, or altitude sickness, is a condition that occurs when your body can't adjust to a high level of altitude.

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Absence of Gamma Globulin in Blood

Agammaglobulinemia is an inherited immune system disorder in which the body is unable to produce antibodies.

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Malignant Hypertension (Arteriolar Nephrosclerosis)

Malignant hypertension is a rare and severe condition in which blood pressure is dangerously high. Learn more about symptoms and treatments.

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Polycythemia Vera

Polycythemia vera (PV) is a bone marrow disorder in which the body produces an excessive amount of red blood cells. Red blood cells are responsible for carrying oxygen to all parts of the body. Blood is carrie...

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Legionnaires' Disease

Legionnaires' disease is a severe type of pneumonia, or lung infection. Learn about its symptoms, causes, treatment, and prevention.

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This feature is for informational purposes only and should not be used to diagnose.
Please consult a healthcare professional if you have health concerns.