Abdominal pain is common and, most of the time, doesn't have a serious cause.

Back pain is fairly common, and is often due to muscle strain or sprain. In students, wearing a heavy backpack is a common cause.

Most causes of chest pain in kids and teens are not serious and will clear up with minimal or no treatment.

Coughing is a symptom, not a disease, and sometimes can help clear the airway.

Babies use crying to communicate, and during the first 3 months of life, they cry a lot. Knowing what to expect can help parents and caregivers manage.

Diarrhea (loose, watery, or more frequent stools) can be a symptom of many conditions, including common infections. Most cases go away in a few days with proper home care.

Dizziness refers to feelings of lightheadedness, vertigo, or disequilibrium.

In most cases, fainting is not a sign of a dangerous problem, but should still be discussed with a doctor.

A fever itself is a symptom, causes no harm, and is often the body's way of fighting infections.

Headaches are common in kids and teens, and can have a wide range of causes. Most can be managed at home.

Malaise and fatigue are common symptoms of a wide-ranging list of ailments. Malaise refers to an overall feeling of discomfort and lack of well-being. Fatigue is extreme tiredness and lack of energy or motivation for everyday activities.

Nausea (stomach upset or feeling queasy) can be caused by many things. Often, it can be managed at home with treatment to prevent dehydration.

A rash is an area of irritated, bumpy, painful, or swollen skin. Most aren't harmful or dangerous.

Learn about some common causes of rectal bleeding, most of which aren't serious.

Seizures can be frightening, but most last only a few minutes and stop on their own.

A sore throat can be caused by many things, from viral and bacterial infections to seasonal allergies and gastroesophageal reflux.

See Dizziness.

Most cases of vomiting are due to viral gastroenteritis ("stomach flu") and can be managed at home with treatment to prevent dehydration.

A to Z Symptoms: Chronic Pain

A to Z Symptoms: Muscle Weakness

Constipation -- having fewer and harder bowel movements (poops) than usual -- is rarely due to a serious condition.