large and small intestine
large and small intestine
The small and large intestines are the parts of the digestive tract that process the food you eat. The gut absorbs nutrients from food. Substances that are not absorbed by the intestine pass through the digestive tract and are passed out as stool during a bowel movement. Diarrhea may be due to abnormalities in the small or large intestine.
Diarrhea -- loose, watery, and possibly more frequent bowel movements -- is a common problem. Sometimes this is the only symptom. Sometimes, it may be accompanied by other symptoms such as nausea, vomiting, abdominal pain, or weight loss.
Fortunately, diarrhea is usually short-lived, lasting no more than a few days. However, if diarrhea persists for more than a few days or weeks, it usually means another problem, such as irritable bowel syndrome (IBS) or a more serious condition, including persistent infection, celiac disease, or inflammatory bowel disease (IBD) .
Symptoms associated with diarrhea (loose, watery stools) may include:
- Abdominal cramping or pain.
- blood in stool.
- There is mucus in the stool.
- Urgent bowel movement is required.
When should you see a doctor?
If you are an adult, see your doctor if:
- Her diarrhea lasted for more than two days and still did not improve.
- You will become dehydrated.
- You have severe abdominal or rectal pain.
- Your stool is bloody or black.
- You have a fever over 39°C.
In children, especially young children, diarrhea can quickly lead to dehydration. Call your doctor if your child's diarrhea does not improve within 24 hours or if your child:
- become dehydrated.
- A fever over 102°F (39°C).
- Bloody or black stools.
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Many diseases and conditions can cause diarrhea, including:
- Virus.Viruses that can cause diarrhea include Norwalk virus (also called norovirus), enteric adenovirus, astrovirus, cytomegalovirus, and viral hepatitis. Rotavirus is a common cause of acute diarrhea in children. The virus that causes coronavirus disease 2019 (COVID-19) has also been associated with gastrointestinal symptoms such as nausea, vomiting and diarrhea.
- Bacteria and parasites.Exposure to certain bacteria, such as E. coli or parasites, through contaminated food or water can cause diarrhea. Diarrhea caused by bacteria and parasites when traveling in developing countries is often called traveler's diarrhea. Clostridium difficile (also known as Clostridium difficile) is another bacteria that causes diarrhea, which can occur after a course of antibiotics or during hospitalization.
- drug.Many medicines, such as antibiotics, can cause diarrhea. Antibiotics clear the infection by killing the bad bacteria, but they also kill the good bacteria. This can disrupt the natural balance of gut bacteria, leading to diarrhea or infections such as Clostridium difficile. Other drugs that can cause diarrhea include cancer drugs and antacids that contain magnesium.
- Lactose intolerance.Lactose is a type of sugar found in milk and other dairy products. People who have trouble digesting lactose can develop diarrhea after consuming dairy products. Lactose intolerance increases with age because levels of the enzyme that helps digest lactose decrease with age.
- fructose.Fructose is a sugar naturally found in fruit and honey. Sometimes it is added to certain drinks as a sweetener. Fructose can cause diarrhea in people with digestive problems.
- Artificial sweeteners.Sorbitol, erythritol and mannitol -- artificial sweeteners that are nonabsorbable sugars found in chewing gum and other sugar-free products -- may cause diarrhea in some healthy people.
- Operation.Diarrhea sometimes occurs during surgery to remove part of the bowel or gallbladder.
- Other digestive disorders.There are many other causes of chronic diarrhea such asirritable bowel syndrome, Crohn's disease, ulcerative colitis, celiac disease, microscopic colitis, and small intestinal bacterial overgrowth (SIBO).
Diarrhea can lead to dehydration, which can be life-threatening if left untreated. Dehydration is especially dangerous for children, the elderly, and those with compromised immune systems.
See your doctor if you notice signs of severe dehydration.
signs of dehydration in adults
- Excessive thirst.
- dry mouth or skin.
- Little or no urination.
- Weakness, dizziness, or lightheadedness.
- Urine is dark in color.
signs of dehydration in infants and toddlers
- Has not had a wet diaper for three hours or more.
- Dry mouth.
- A fever over 102°F (39°C).
- cry without tears
- Drowsiness, sluggishness, or irritability.
- Sunken abdomen, eyes, or cheeks.
prevent infectious diarrhea
Wash your hands to prevent the spread of infectious diarrhea. To ensure adequate hand washing:
- Wash often.Wash your hands before and after preparing food. Wash your hands after handling raw meat, using the toilet, changing diapers, sneezing, coughing, and blowing your nose.
- Lather up with soap for at least 20 seconds.After you apply soap to your hands, rub your hands together for at least 20 seconds. That's roughly the time it would take to sing "Happy Birthday" twice.
- Use hand sanitizer when cleaning is not possible.If you cannot reach a sink, use an alcohol-based hand sanitizer. Use hand sanitizer, such as hand sanitizer, making sure to cover the front and back of your hands. Use products with at least 60 percent alcohol.
Using one of two approved vaccines can help protect your child from rotavirus, the most common cause of viral diarrhea in children. Ask your baby's doctor about your baby's vaccinations.
Preventing Travelers' Diarrhea
Diarrhea is common among people who travel to countries with poor sanitation and contaminated food. To reduce your risk:
- Be mindful of what you eat.Eat hot, cooked food. Avoid raw fruits and vegetables unless you can peel them yourself. Do not eat raw or undercooked meat or dairy products.
Be mindful of what you drink.Drink bottled water, soda, beer, or wine from the original container. Do not drink tap water and do not use ice cubes. Also, use bottled water to brush your teeth. Keep your mouth shut when you shower.
Beverages brewed with boiling water, such as coffee and tea, are likely safe. Remember that alcohol and caffeine can make diarrhea worse and make dehydration worse.
- Ask your healthcare team about antibiotics.If you are going to a developing country for an extended period, ask a member of your health team about antibiotics before your trip, especially if you have a compromised immune system.
- Heed travel warnings.The U.S. Centers for Disease Control and Prevention maintains a travel health website with country-by-country disease alerts. If you plan to travel outside the United States, please review the warnings and risk reduction tips there.
Mayo Clinic staff
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August 22, 2023
- diarrhea. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/digestive-diseases/diarrea. Date of access: April 27, 2023.
- Diarrheal disease: acute and chronic. American College of Gastroenterology. https://gi.org/topics/diarrea-acute-and-chronic/. Date of access: April 27, 2023.
- Ask a Mayo expert. COVID-19: management and follow-up (adults). Mayo Clinic; 2021
- diarrhea. Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/gastrointestinal disorders/symptoms - gastrointestinal disorders/diarrhea. Date of access: April 27, 2023.
- Centers for Disease Control and Prevention, Travelers' Diarrhea. https://wwwnc.cdc.gov/travel/yellowbook/2020/preparing-international-travelers/travelers-diarrea. Date of access: April 27, 2023.
- Khanna S (expert opinion). Mayo Clinic. May 14, 2021.
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