Symptoms and Causes

What Is Hypothermia Hypothermia happens when your body temperature falls below 95°F (35°C), which is much lower than the normal body temperature of 98.6°F (37°C). This…

What Is Sickle Cell Disease Sickle cell disease is a group of inherited blood disorders. The most common type is sickle cell anemia. This condition changes…

Overview The heart has four chambers—two upper ones (atria) and two lower ones (ventricles). Heart rhythm normally starts in the right upper chamber at the sinus…

Overview Chest pain describes discomfort that occurs between your neck and abdomen. This pain varies in how it feels – it might be sharp, dull, constant,…

Overview Tension-type headaches are the most common headache variety, causing mild to moderate pain often felt as a tight band around the head. Though widespread, the…

Understanding Airway Infections A healthy airway allows air to move freely through the throat and into the lungs. In children, these passages are naturally smaller than…

Overview Burning mouth syndrome refers to a persistent or recurring burning sensation in the mouth that lacks an identifiable cause. This uncomfortable feeling may affect the…

Overview Barrett’s esophagus occurs when the normal flat pink lining of the esophagus (the tube connecting mouth to stomach) becomes damaged by acid reflux, causing the…

Overview Anaphylaxis occurs when the body has a severe allergic reaction. The immune system mistakenly identifies a harmless substance as dangerous and releases chemicals to fight…

Overview Hepatitis B is a liver infection caused by HBV (hepatitis B virus). The infection comes in two forms: acute and chronic. Acute hepatitis B resolves…