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.
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 steatotic liver disease? Your liver is the largest organ inside your body. It helps you digest food, store energy, and remove harmful substances ( ...
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 ...
What are streptococcal infections? Strep is short for Streptococcus, a type of bacteria that often lives in your nose and throat. Most strep infections ...
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 ...
What is stuttering? Stuttering is a speech disorder. It involves interruptions in the flow of speech. These interruptions are called disfluencies. They ...
What is sudden cardiac arrest (SCA)? Sudden cardiac arrest (SCA) is a condition in which the heart suddenly stops beating. When that happens, blood stops ...
Sudden infant death syndrome (SIDS) is the sudden, unexplained death of an infant younger than one year old. Some people call SIDS "crib death" because many babies ...
What is suicide? Suicide is the taking of one's own life. It is a death that happens when someone harms themselves because they want to end their life. ...
There are many reasons to have surgery. Some operations can relieve or prevent pain. Others can reduce a symptom of a problem or improve some body function. ...
How well you and your doctor or provider communicate with each other is one of the most important parts of getting good health care. Being prepared can help ...
Can a tan be healthy? Some people think that tanning gives them a healthy glow. But tanning, either outdoors or indoors with a tanning bed, is not healthy ...
What is depression in teens? Depression in teens (ages 13-17) is a serious medical illness. It's more than just a feeling of being sad or "blue" for a few ...
What is teen sexual health? Teen sexual health is about how sex affects your physical and emotional health. It means knowing how to form healthy relationships ...
