Browse comprehensive, doctor-reviewed information on 50 health conditions.
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, hyperacti...
Allergies occur when the immune system reacts to a foreign substance that is typically harmless. Common allergens includ...
Alzheimer's disease is a progressive neurological disorder that causes the brain to shrink and brain cells to die. It is...
Anemia is a condition in which you lack enough healthy red blood cells to carry adequate oxygen to body tissues. It can ...
Anxiety disorders are a group of mental health conditions characterized by excessive worry, fear, and related behavioral...
Asthma is a chronic respiratory condition in which the airways narrow and swell and may produce extra mucus. This can ma...
Breast cancer is cancer that forms in the cells of the breasts. It is the most common cancer in women worldwide, though ...
Bronchitis is an inflammation of the lining of the bronchial tubes, which carry air to and from the lungs. Acute bronchi...
Celiac disease is an autoimmune disorder where eating gluten triggers an immune response in the small intestine. Over ti...
Chronic back pain is pain in the back that persists for 12 weeks or longer, even after an initial injury or underlying c...
Chronic kidney disease (CKD) is a condition characterized by a gradual loss of kidney function over time. In early stage...
Colorectal cancer is cancer that occurs in the colon or rectum. It is the third most common cancer in both men and women...
Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes obstructed airflow from ...
Coronary heart disease (CHD) is a disease in which plaque builds up inside the coronary arteries, which supply oxygen-ri...
Crohn's disease is a type of inflammatory bowel disease (IBD) that causes inflammation of the digestive tract. It can le...
Eczema (atopic dermatitis) is a chronic skin condition that makes the skin red, inflamed, and itchy. It is common in chi...
Endometriosis is a disorder in which tissue similar to the tissue that normally lines the inside of the uterus grows out...
Epilepsy is a central nervous system disorder in which brain activity becomes abnormal, causing seizures or periods of u...
Fibromyalgia is a disorder characterized by widespread musculoskeletal pain accompanied by fatigue, sleep, memory, and m...
Gastroesophageal reflux disease (GERD) is a chronic digestive disease that occurs when stomach acid flows back into the ...
Gout is a form of inflammatory arthritis characterized by sudden, severe attacks of pain, swelling, redness, and tendern...
Hepatitis C is a viral infection that causes liver inflammation. The hepatitis C virus (HCV) spreads through contaminate...
High cholesterol is a condition where you have too much cholesterol in your blood. Cholesterol is a waxy substance found...
HIV (human immunodeficiency virus) is a virus that attacks the immune system. If not treated, it can lead to AIDS (acqui...
Hypertension (high blood pressure) is a common condition where the long-term force of the blood against the artery walls...
Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormones. This can slow down ma...
Irritable bowel syndrome (IBS) is a common disorder that affects the large intestine. Signs and symptoms include crampin...
Kidney stones are hard deposits made of minerals and salts that form inside the kidneys. They can affect any part of the...
Lung cancer is a type of cancer that begins in the lungs. It is the leading cause of cancer deaths in the United States....
Systemic lupus erythematosus (lupus) is a chronic autoimmune disease that can damage any part of the body, including ski...