MedlinePlus is a service of the National Library of Medicine (NLM), the world's largest medical library, which is part of the National Institutes of Health (NIH). It was built as an online health information resource for patients and their families and friends.
MedlinePlus presents high-quality, easy to understand, relevant health and wellness information that is trusted.
What is sexual assault? Sexual assault is any kind of sexual activity, contact, or experience that happens without your consent. That means the sexual ...
What are sexually transmitted infections (STIs)? Sexually transmitted infections (STIs) are infections that are passed from one person to another through ...
What is shingles? Shingles (herpes zoster) is an infection that causes a painful rash. It is caused by the varicella-zoster virus (VZV). This is the same ...
What is sickle cell disease (SCD)? Sickle cell disease (SCD) is a group of inherited red blood cell disorders. If you have SCD, there is a problem with ...
What is Sjogren's syndrome? Sjogren's syndrome, also called Sjogren's disease, is a chronic (long-lasting) autoimmune disease. When you have an autoimmune ...
What are skin infections? Your skin is your body's largest organ. It has many different functions, including covering and protecting your body. It helps ...
What is sleep? While you are sleeping your brain and body functions are still active. Sleep is a natural process that helps your body restore energy, ...
What are the health effects of smoking? There's no way around it; smoking is bad for your health. It harms nearly every organ of the body, even some that ...
Your soft tissues connect, support, or surround other tissues. Examples include your muscles, tendons, fat, and blood vessels. Soft tissue sarcoma is a cancer ...
Your spinal cord is a bundle of nerves that runs down the middle of your back. It carries signals back and forth between your body and your brain. A spinal ...
What is spinal muscular atrophy (SMA)? Spinal muscular atrophy (SMA) is a group of genetic diseases that damages and kills motor neurons. Motor neurons ...
A sprain is a stretched or torn ligament. Ligaments are tissues that connect bones at a joint. Falling, twisting, or getting hit can all cause a sprain. ...
What are Staphylococcal (staph) infections? Staphylococcus (staph) is a group of bacteria. There are more than 30 types. A type called Staphylococcus aureus ...
What is cholesterol? Cholesterol is a waxy, fat-like substance that's found in all the cells in your body. Your body needs some cholesterol to work properly. ...
What is a stillbirth? If you lose a fetus at or after the 20th week of pregnancy, it's called a stillbirth. A stillbirth can occur before or during delivery ...
The stomach is an organ between the esophagus and the small intestine. It mixes food with stomach acid and helps digest protein. Stomach cancer mostly affects ...
Strep is short for Streptococcus, a type of bacteria. There are several types. Two of them cause most of the strep infections in people: group A and group ...
What is stress? Stress is how your brain and body respond to a challenge or demand. When you are stressed, your body releases certain hormones. Hormones ...
What is a stroke? A stroke happens when there is a loss of blood flow to part of the brain. Your brain cells cannot get the oxygen and nutrients they ...
What is stroke rehabilitation? Stroke rehabilitation is a program for people who have had a stroke. A stroke happens when there is a loss of blood flow ...
