Signs and symptoms associated with diarrhea may include:

• Loose, watery stools
• Abdominal cramps
• Abdominal pain
• Fever
• Blood in the stool
• Mucus in the stool
• Bloating
• Nausea
• Urgent need to have a bowel movement

A number of diseases and conditions can cause diarrhea, including

• Viruses. Viruses that can cause diarrhea include Norwalk virus, cytomegalovirus and viral hepatitis. Rotavirus is a common cause of acute childhood diarrhea.
• Bacteria and parasites. Contaminated food or water can transmit bacteria and parasites to your body. When traveling in developing countries, diarrhea caused by bacteria and parasites is often called traveler's diarrhea. Clostridium difficile is another type of bacteria that can cause serious infections that cause diarrhea, and it can occur after a course of antibiotics or during a hospitalization.
• Medications. Many medications, such as antibiotics, can cause diarrhea. Antibiotics destroy both good and bad bacteria, which can disturb the natural balance of bacteria in your intestines. Other drugs that cause diarrhea are cancer drugs and antacids with magnesium.
• Lactose intolerance. Lactose is a sugar found in milk and other dairy products. People who have difficulty digesting lactose have diarrhea after eating dairy products. Lactose intolerance can increase with age because levels of the enzyme that helps digest lactose drop after childhood.
• Fructose. Fructose is a sugar found naturally in fruits and honey. It's sometimes added as a sweetener to certain beverages. In people who have trouble digesting fructose, it can lead to diarrhea.
• Artificial sweeteners. Sorbitol and mannitol — artificial sweeteners found in chewing gum and other sugar-free products — can cause diarrhea in some otherwise healthy people.
• Surgery. Abdominal or gallbladder removal surgeries can sometimes cause diarrhea.
• Other digestive disorders. Chronic diarrhea has a number of other causes, such as Crohn's disease, ulcerative colitis, celiac disease, microscopic colitis and irritable bowel syndrome.

Diarrhea can cause dehydration, which can be life-threatening if untreated. Dehydration is particularly dangerous in children, older adults and those with weakened immune systems.

If you have signs of serious dehydration, seek medical help.

Indications of dehydration in adults

These include:

• Excessive thirst
• Dry mouth or skin
• Little or no urination
• Weakness, dizziness or lightheadedness
• Fatigue
• Dark-colored urine

Indications of dehydration in infants and young children

These include:

• Not having a wet diaper in three or more hours
• Dry mouth and tongue
• Fever above 102 F (39 C)
• Crying without tears
• Drowsiness, unresponsiveness or irritability
• Sunken appearance to the abdomen, eyes or cheeks