Diarrhea: Causes, Symptoms, and Treatment
Medically reviewed by Sumiran Racherla, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Diarrhea?
A family doctor or other primary care doctor usually treats diarrhea. If it lasts for weeks or keeps coming back, you may see a gastroenterologist, a doctor who treats digestive problems. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is diarrhea?
Diarrhea means loose, watery stools (bowel movements). You have it if you have loose stools three or more times in one day.
Acute diarrhea is diarrhea that lasts a short time. It usually lasts about one or two days, but it may last longer. Chronic diarrhea lasts at least four weeks.
Symptoms
Common signs include:
- Loose, watery stools three or more times a day, or more often than what is normal for you.
- An urgent need to use the bathroom.
- Cramping or pain in the belly.
- Fever, chills, or bloody stools if an infection is the cause.
Diarrhea can also cause dehydration, which means your body does not have enough fluid to work properly. Dehydration can be serious, especially in children and older adults. Signs of dehydration include:
- Very strong thirst or a dry mouth.
- Peeing less than usual.
- Dark urine.
- In babies and young children, no wet diapers for 3 hours or more.
Causes and who gets it
Short-term diarrhea is most often caused by a stomach virus, food poisoning, or medicine side effects. A stomach virus, called viral gastroenteritis, is an infection of your intestines. Food poisoning is an infection or irritation of your digestive tract that spreads through foods or drinks. Some medicines can cause it. Examples are antibiotics and cancer drugs.
Long-term diarrhea has many causes. They include infections, food allergies, and surgery on the belly. Crohn's disease and ulcerative colitis can also cause it. Sometimes no cause can be found.
Diarrhea is more likely to cause health problems if you are pregnant or over age 65. The same is true if you take antibiotics or have a weak immune system.
How doctors diagnose it
If your diarrhea goes away within a few days, finding the cause is usually not necessary. Otherwise, your health care provider may:
- Do a physical exam and ask about your medicines.
- Test your stool or blood for germs or signs of disease.
- Ask you to stop eating certain foods to see whether the diarrhea goes away.
Treatment
In most cases, you can treat acute diarrhea at home without medical treatment. The key is replacing lost fluids and electrolytes (body salts and minerals) to prevent dehydration.
- Adults can drink water, fruit juices, sports drinks, sodas without caffeine, and salty broths.
- As symptoms improve, you can eat soft, bland food.
- Children should be given oral rehydration solutions, liquids that contain glucose and electrolytes.
- In most cases, you can safely treat acute diarrhea with loperamide or bismuth subsalicylate, You can buy them without a prescription.
Doctors usually advise against these medicines for babies, kids, or people with bloody stools or fever. Severe dehydration may need IV fluids, which go into a vein. Antibiotics or other medicines may help with some gut infections.
When to see a doctor
Diarrhea can become dangerous if it leads to severe dehydration. Talk with a doctor right away if you or someone in your care has:
- Signs of dehydration, listed above.
- Vomiting again and again.
- Severe pain in the belly or rectum.
- Stools that are black and tarry, or that contain red blood or pus.
- Diarrhea lasting more than 2 days (adults), or more than a day (infants and children).
- A fever of 102 degrees or higher.
Diarrhea is especially dangerous in newborns and infants and can lead to severe dehydration in just a day or two. Call 911 or go to the emergency room if someone faints, loses consciousness, or is confused and hard to wake up.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either kind of doctor can review your symptoms and medicines, order tests, and check for dehydration. They can also refer you to a gastroenterologist if the diarrhea lasts or keeps coming back.
Common questions
How long does diarrhea last?
Acute diarrhea usually lasts about one or two days, but it may last longer. Diarrhea lasting more than a few days may be a sign of a more serious problem.
Can I take medicine for diarrhea?
In most cases, you can safely treat short-term (acute) diarrhea with loperamide or bismuth subsalicylate. See a doctor if the diarrhea gets worse or lasts more than 2 days while you take one.
Can diarrhea be prevented?
Some types can be. Washing your hands can lower your chances of getting or spreading infections that can cause diarrhea. Vaccines for rotavirus are given to babies in two or three doses.
Do probiotics help with diarrhea?
Not clearly. Many doctors and professional groups do not think the evidence supports probiotics for diarrhea. Researchers are still studying them. Talk with your doctor before using them.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
