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Psoriasis is a skin disease that causes itchy or sore patches of thick, red skin with silvery scales. You usually get them on your elbows, knees, scalp, back, ...
Psychotic disorders are severe mental disorders that cause abnormal thinking and perceptions. People with psychoses lose touch with reality. Two of the main symptoms ...
Puberty is the time in life when a boy or girl becomes sexually mature. It is a process that usually happens between ages 10 and 14 for girls and ages 12 and ...
What are pubic lice? Pubic lice (also called crabs) are tiny insects which usually live in the pubic or genital area of humans. They are also sometimes ...
What is a pulmonary embolism (PE)? A pulmonary embolism (PE) is a sudden blockage in a lung artery. It usually happens when a blood clot breaks loose and ...
Pulmonary fibrosis is a condition in which the tissue deep in your lungs becomes scarred over time. This tissue gets thick and stiff. That makes it hard for you ...
What is pulmonary hypertension? Pulmonary hypertension, sometimes called PH, is a serious condition that affects the blood vessels in the lungs. It develops ...
What is pulmonary rehabilitation? Pulmonary rehabilitation, also known as pulmonary rehab or PR, is a program for people who have chronic (ongoing) breathing ...
Tobacco use is the most common preventable cause of death. About half of the people who don't quit smoking will die of smoking-related problems. Quitting smoking ...
Rabies is a deadly animal disease caused by a virus. It can happen in wild animals, including raccoons, skunks, bats and foxes, or in dogs, cats or farm animals. ...
Radiation is a type of energy. People are exposed to small amounts of radiation every day from sources such as sunlight. A radiation emergency would involve larger ...
What is radiation? Radiation is energy. It travels in the form of energy waves or high-speed particles. Radiation can occur naturally or be man-made. ...
What is radiation therapy? Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from spreading. ...
What is radon? Radon is a naturally occurring radioactive gas. It is invisible and has no odor or taste. It comes from the normal decay of uranium and ...
A rare disease is one that affects fewer than 200,000 people in the United States. There are nearly 7,000 rare diseases. More than 25 million Americans ...
A rash is an area of irritated or swollen skin. Many rashes are itchy, red, painful, and irritated. Some rashes can also lead to blisters or patches of ...
What is Raynaud phenomenon? Raynaud phenomenon is a condition that affects your blood vessels (the tubes that your blood flows through). It causes your ...
The rectum is the lower part of your large intestine where your body stores stool. Problems with the rectum are common. They include hemorrhoids, abscesses, ...
What are reflux (GER) and GERD? The esophagus is the tube that carries food from your mouth to your stomach. If your child has reflux, his or her stomach ...
What are reflux and GERD? The esophagus is the tube that carries food from your mouth to your stomach. If your baby has reflux, his or her stomach contents ...
