Find out the symptoms of STDs and what you can do to prevent them, along with the treatments if you're diagnosed with one.
Disease
Sezary syndrome
Find out more about the symptoms, diagnosis and treatment of this rare type of cancer.
Disease
Shaken baby syndrome
Understand why shaking a baby can cause brain damage, and why getting immediate medical care can save a child's life or prevent serious health problems.
Disease
Shellfish allergy
It's possible to be allergic to some types of shellfish without reacting to other types. Learn more about this common food allergy.
Disease
Shigella infection
This infection of the intestine causes diarrhea. Learn the symptoms, treatments and ways to help prevent it.
Disease
Shin splints
This pain along the shin bone is common in runners, dancers and military trainees. Learn how to prevent shin splints.
Disease
Shingles
Learn more about symptoms, causes, treatment and vaccine prevention of this painful condition affecting the nerves.
Disease
Short bowel syndrome
This digestive condition happens when part of the small intestine is missing or damaged, either at birth or after surgery. The syndrome keeps you from absorbing needed nutrients.
Disease
Sick sinus syndrome
This heart rhythm disorder causes slow, paused or irregular heartbeats. Learn the symptoms and how it's treated.
Disease
Sickle cell anemia
Learn about the symptoms, causes and treatment of this inherited blood disorder that, in the United States, is more common among Black people.
Disease
Sinus headaches
Sinus headaches are often to blame for headache with facial pain — but that pain might actually be a migraine.
Disease
Sjogren's syndrome
If you're bothered by dry eyes and mouth, talk to your doctor about whether you have the autoimmune condition Sjogren's syndrome.