Medically reviewed on Oct 25, 2018
Everyone occasionally has diarrhea — loose, watery and possibly more-frequent bowel movements.
In most cases, diarrhea lasts a couple of days. But when diarrhea lasts for weeks, it can indicate a serious disorder, such as a persistent infection, inflammatory bowel disease, or a less serious condition, such as irritable bowel syndrome.
The small intestine and colon are components of your digestive tract, which processes the foods you eat. The small intestine and colon extract nutrients and water from the foods. What isn't absorbed by the small intestine and colon continues along the digestive tract and is expelled as stool during a bowel movement.
Signs and symptoms associated with diarrhea may include:
- Loose, watery stools
- Abdominal cramps
- Abdominal pain
- Blood in the stool
- Urgent need to have a bowel movement
When to see a doctor
If you're an adult, see your doctor if:
- Your diarrhea persists beyond two days
- You become dehydrated
- You have severe abdominal or rectal pain
- You have bloody or black stools
- You have a fever above 102 F (39 C)
In children, particularly young children, diarrhea can quickly lead to dehydration. Call your doctor if your child's diarrhea doesn't improve within 24 hours or if your baby:
- Becomes dehydrated
- Has a fever above 102 F (39 C)
- Has bloody or black stools
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. Parasites such as Giardia lamblia and cryptosporidium can cause diarrhea.
Common bacterial causes of diarrhea include campylobacter, salmonella, shigella and Escherichia coli. When traveling in developing countries, diarrhea caused by bacteria and parasites is often called traveler's diarrhea. Clostridium difficile infection can occur, especially after a course of antibiotics.
- 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.
Your body makes an enzyme that helps digest lactose, but for most people, the levels of this enzyme drop off rapidly after childhood. This causes an increased risk of lactose intolerance as you age.
- Fructose. Fructose, a sugar found naturally in fruits and honey and added as a sweetener to some beverages, can cause diarrhea in people who have trouble digesting it.
- 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. Some people have diarrhea after undergoing abdominal surgery or gallbladder removal surgery.
- 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
- Excessive thirst
- Dry mouth or skin
- Little or no urination
- Weakness, dizziness or lightheadedness
- Dark-colored urine
Indications of dehydration in infants and young children
- 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
Preventing viral diarrhea
Wash your hands to prevent the spread of viral diarrhea. To ensure adequate hand-washing:
- Wash frequently. Wash your hands before and after preparing food. Wash your hands after handling uncooked meat, using the toilet, changing diapers, sneezing, coughing and blowing your nose.
- Lather with soap for at least 20 seconds. After putting soap on your hands, rub your hands together for at least 20 seconds. This is about as long as it takes to sing "Happy Birthday" twice through.
- Use hand sanitizer when washing isn't possible. Use an alcohol-based hand sanitizer when you can't get to a sink. Apply the hand sanitizer as you would hand lotion, making sure to cover the fronts and backs of both hands. Use a product that contains at least 60 percent alcohol.
You can help protect your infant from rotavirus, the most common cause of viral diarrhea in children, with one of two approved vaccines. Ask your baby's doctor about having your baby vaccinated.
Preventing traveler's diarrhea
Diarrhea commonly affects people who travel to countries where there's inadequate sanitation and contaminated food. To reduce your risk:
- Watch what you eat. Eat hot, well-cooked foods. Avoid raw fruits and vegetables unless you can peel them yourself. Also avoid raw or undercooked meats and dairy foods.
Watch what you drink. Drink bottled water, soda, beer or wine served in its original container. Avoid tap water and ice cubes. Use bottled water even for brushing your teeth. Keep your mouth closed while you shower.
Beverages made with boiled water, such as coffee and tea, are probably safe. Remember that alcohol and caffeine can aggravate diarrhea and dehydration.
- Ask your doctor about antibiotics. If you're traveling to a developing country for an extended time, ask your doctor about starting antibiotics before you go, especially if you have a weakened immune system. In certain cases, taking an antibiotic might reduce your risk of traveler's diarrhea.
- Check for travel warnings. The Centers for Disease Control and Prevention maintains a travelers' health website where disease warnings are posted for various countries. If you're planning to travel outside of the United States, check there for warnings and tips for reducing your risk.
Besides conducting a physical exam and reviewing your medications, your doctor might order tests to determine what's causing your diarrhea. They include:
- Blood test. A complete blood count test can help determine what's causing your diarrhea.
- Stool test. Your doctor might recommend a stool test to determine whether a bacterium or parasite is causing your diarrhea.
Flexible sigmoidoscopy or colonoscopy. Your doctor might recommend one of these procedures to look at the lining of your colon and provide biopsies if no cause is evident for persistent diarrhea.
Both procedures involve using a thin, lighted tube with a lens on the end to look inside your colon.
Most cases of diarrhea clear on their own within a couple of days without treatment. If you've tried lifestyle changes and home remedies for diarrhea without success, your doctor might recommend medications or other treatments.
Antibiotics might help treat diarrhea caused by bacteria or parasites. If a virus is causing your diarrhea, antibiotics won't help.
Treatment to replace fluids
Your doctor likely will advise you to replace the fluids and salts. For most adults, that means drinking water, juice or broth. If drinking liquids upsets your stomach or causes diarrhea, your doctor might recommend getting fluids through a vein in your arm (intravenously).
Water is a good way to replace fluids, but it doesn't contain the salts and electrolytes — minerals such as sodium and potassium — you need to maintain the electric currents that keep your heart beating. You can help maintain your electrolyte levels by drinking fruit juices for potassium or eating soups for sodium. Certain fruit juices, such as apple juice, might make diarrhea worse.
For children, ask your doctor about using an oral rehydration solution, such as Pedialyte, to prevent dehydration or replace lost fluids.
Adjusting medications you're taking
If your doctor determines that an antibiotic caused your diarrhea, your doctor might lower your dose or switch to another medication.
Treating underlying conditions
If your diarrhea is caused by a more serious condition, such as inflammatory bowel disease, your doctor will work to control that condition. You might be referred to a specialist, such as a gastroenterologist, who can help devise a treatment plan for you.
Lifestyle and home remedies
Most diarrhea cases clear up on their own within a few days. To help you cope with your signs and symptoms until the diarrhea goes away, try to:
- Drink plenty of clear liquids, including water, broths and juices. Avoid caffeine and alcohol.
- Add semisolid and low-fiber foods gradually as your bowel movements return to normal. Try soda crackers, toast, eggs, rice or chicken.
- Avoid certain foods such as dairy products, fatty foods, high-fiber foods or highly seasoned foods for a few days.
Ask about anti-diarrheal medications. Over-the-counter (OTC) anti-diarrheal medications, such as loperamide (Imodium A-D) and bismuth subsalicylate (Pepto-Bismol), might help reduce the number of watery bowel movements and control severe symptoms.
Certain medical conditions and infections — bacterial and parasitic — can be worsened by these medications because they prevent your body from getting rid of what's causing the diarrhea. Also, these drugs aren't always safe for children. Check with your doctor before taking these medications or giving them to a child.
Consider taking probiotics. These microorganisms help restore a healthy balance to the intestinal tract by boosting the level of good bacteria. Probiotics are available in capsule or liquid form and are also added to some foods, such as certain brands of yogurt.
Studies confirm that some probiotics might be helpful in treating antibiotic-associated diarrhea and infectious diarrhea. However, further research is needed to better understand which strains of bacteria are most helpful or what doses are needed.
Preparing for an appointment
You might start by seeing your primary care practitioner. If you have persistent diarrhea, you may be referred to a doctor who specializes in the digestive system (gastroenterologist).
Here's some information to help you get ready for your appointment.
What you can do
When you make the appointment, ask if there's anything you need to do in advance, such as fast before certain tests. Make a list of:
- Your symptoms, including when they began and any that may seem unrelated to the reason for which you scheduled the appointment.
- Key personal information, including any major stresses, recent life changes or travel.
- Medications, vitamins or supplements you take, including doses. If you've recently taken an antibiotic, note what kind, for how long and when you stopped.
- Questions to ask your doctor.
For diarrhea, some basic questions to ask your doctor include:
- What is likely causing my diarrhea?
- Could my diarrhea be caused by a medication I'm taking?
- What tests do I need?
- Is my diarrhea likely temporary or chronic?
- What is the best course of action?
- What are the alternatives to the primary approach that you're suggesting?
- I have other health conditions. How can I best manage them with the diarrhea?
- Are there restrictions I should follow?
- May I take medication such as loperamide to slow the diarrhea down?
- Should I see a specialist?
Don't hesitate to ask other questions.
What to expect from your doctor
Your doctor is likely to ask you questions, including:
- When did your symptoms begin?
- Have your symptoms been continuous or occasional?
- How severe are your symptoms?
- What, if anything, seems to improve your symptoms?
- What, if anything, appears to worsen your symptoms?
- Does your diarrhea awaken you at night?
- Do you see blood, or are your bowel movements black in color?
- Have you recently been around anyone who has diarrhea?
- Have you recently stayed in a hospital or nursing home?
- Have you take antibiotics recently?
What you can do in the meantime
While you wait for your appointment, you may ease your symptoms if you:
- Drink more fluids. To help avoid dehydration, drink water, juice and broth.
- Avoid foods that can aggravate diarrhea. Avoid fatty, high-fiber or highly seasoned foods.