What makes you have diarrhea after eating

What Is Diarrhea?

When you have diarrhea, your bowel movements (or stools) are loose and watery. It’s common and usually not serious.

Many people get diarrhea a few times a year. It normally lasts 2 to 3 days. Some people get it more often. It could be because they have irritable bowel syndrome (IBS) or other conditions.

What Causes Diarrhea?

Usually, diarrhea happens because of a virus that gets into your gut. Some people call it "intestinal flu" or "stomach flu."

Other causes include:

  • Alcohol abuse
  • Allergies to certain foods
  • Diabetes
  • Diseases of the intestines (such as Crohn's disease or ulcerative colitis)
  • Eating foods that upset the digestive system
  • Infection by bacteria (the cause of most types of food poisoning) or other organisms
  • Laxative abuse
  • Medications
  • Overactive thyroid (hyperthyroidism)
  • Radiation therapy
  • Running (Some people get “runner’s diarrhea” for reasons that aren’t clear.)
  • Some cancers
  • Surgery on your digestive system
  • Trouble absorbing certain nutrients, also called “malabsorption”

Diarrhea may also follow constipation, especially for people who have irritable bowel syndrome.

Symptoms of Diarrhea

You may have:

  • Bloating in your belly
  • Cramps
  • Thin or loose stools
  • Watery stools
  • An urgent feeling that you need to have a bowel movement
  • Nausea and throwing up

More serious symptoms include:

  • Blood or mucus in your stool
  • Weight loss
  • Fever

If you have watery stools more than three times a day and you're not drinking enough fluids, you could become dehydrated. That can be a serious problem if it's not treated.

When Should I Call My Doctor?

Call your doctor right away if you have:

  • Blood in your diarrhea or black, tarry stools
  • A fever that is high (above 101 F) or that lasts more than 24 hours
  • Diarrhea lasting longer than 2 days
  • Nausea or throwing up that prevents you from drinking liquids to replace lost fluids
  • Severe pain in your belly (especially the right lower quadrant) or rear end
  • Diarrhea after coming back from a foreign country

Also, call your doctor right away if you have diarrhea and any of these signs of dehydration:

  • Dark urine
  • Smaller than usual amounts of urine or, in a child, fewer wet diapers than usual
  • Rapid heart rate
  • Headaches
  • Dry skin
  • Crankiness
  • Confusion

Diarrhea Diagnosis

Your doctor will ask about your medical history and what medications you take, as well as what you’ve eaten or had to drink recently. They will give you a physical exam to look for signs of dehydration or belly pain.

Certain tests can help pinpoint the cause of your diarrhea, including:

  • Blood tests to look for certain diseases or disorders
  • Colonoscopy, in rare cases, in which your doctor looks inside your colon with a thin, flexible tube that holds a tiny camera and light. They can also use this device to take a small sample of tissue. Or your doctor might need to do only a sigmoidoscopy, which looks at just the lower colon.
  • Stool tests to look for bacteria or parasites

Treatment for Diarrhea

If your case is mild, you may not need to take anything. Adults can take an over-the-counter medicine such as bismuth subsalicylate or loperamide, which you can get as liquids or tablets.

You also need to stay hydrated. You should drink at least six 8-ounce glasses of fluids each day. Choose electrolyte replacement drinks or soda without caffeine. Chicken broth (without the fat), tea with honey, and sports drinks are also good choices. Instead of drinking liquids with your meals, drink liquids between meals. Sip small amounts of fluids often. Liquid probiotics may also help.

How Can I Feel Better?

Your rectal area may become sore because of all the bowel movements that diarrhea brings. You may have itching, burning, or pain when you go to the bathroom.

For relief, take a warm bath or sitz bath. Afterward, pat the area dry (don’t rub) with a clean, soft towel. You may also try using a hemorrhoid cream or petroleum jelly on the affected area. If this continues for several days, you should contact your doctor.

What makes you have diarrhea after eating

Diarrhea after every meal may indicate a larger digestive issue.

Image Credit: Ratree Khotchalee/iStock/GettyImages

In This Article

  • Digestive Disorders
  • Gallbladder or Pancreas Issues
  • IBS
  • Food Allergies or Intolerances
  • When to See a Doctor

Nearly everyone experiences diarrhea from time to time, but diarrhea after every meal can be a sign of a larger problem. It may also take a bit of detective work to diagnose, as there are a number of possible causes of diarrhea after eating.

When Diarrhea After Eating Becomes an Issue

The Cleveland Clinic defines mild diarrhea as loose and watery bowel movements that may be accompanied by cramping, bloating, urgency, nausea and vomiting. The condition progresses to severe diarrhea if, in addition to those symptoms, you have undigested food, blood or mucus in your stool, experience weight loss or dehydration or have severe pain or fever.

The primary symptom of viral gastroenteritis — commonly called stomach flu — is diarrhea that usually resolves within a few (miserable) days. In the case of food poisoning, diarrhea and other symptoms may last a couple of weeks.

But if diarrhea persists almost every time you eat, certain clues can help you and your doctor get to the root cause.

1. Digestive Diseases or Disorders

"The first thing I would wonder is if you have an underlying issue that has been undiagnosed," says Will Bulsiewicz, MD, a gastroenterologist with Lowcountry Gastroenterology in Mount Pleasant, South Carolina, and author of ​The Fiber Fueled Cookbook​.

Some possibilities, he says, include:

  • Celiac disease
  • An infection such as Clostridium difficile (C. diff.)
  • A parasitic infection such as Giardia
  • Inflammatory bowel disease (IBD)
  • Microscopic colitis

Symptoms of these conditions include blood in the stool, which can indicate an IBD such as ulcerative colitis or Crohn's disease, anemia or symptoms of anemia such as fatigue, lightheadedness, weakness and weight loss.

Diarrhea that disrupts sleep in the middle of the night is one sign of microscopic colitis, an autoimmune condition.

Chronic diarrhea may also affect people who have gallbladder problems or have had their gallbladder removed.

2. Gallbladder or Pancreas Issues

"That is not uncommon — about 10 percent of people who have had their gallbladder removed develop chronic diarrhea, or bile salt enteropathy," Dr. Bulsiewicz says, adding that "it's quite easy to treat once it's diagnosed."

In some people, the underlying problem may stem from pancreatic insufficiency, which impairs the absorption of fats in the small intestine.

3. Could It Be IBS?

Irritable bowel syndrome (IBS) is the most common cause of chronic diarrhea after eating. Though less debilitating than IBD or celiac disease, IBS can still have a serious negative impact on quality of life.

People with IBS may have what Dr. Bulsiewicz calls an overactive gastrocolic reflex.

"The entire gut is wired together — the stomach talks to the colon, the colon talks to the stomach," he explains. "When the stomach receives food, it sends a signal to the colon to start to move and make room."

Normally, this reflex triggers a healthy bowel movement after eating. But in someone with IBS, the reflex is over-stimulated, which leads to diarrhea after a meal.

4. Food Allergies and Intolerances

If the diarrhea follows a specific pattern — say, chronic but sporadic — that could indicate a food intolerance or food allergy.

According to Mayo Clinic, people with a food intolerance may be able to ingest small amounts of those foods without consequence, but a true food allergy will be set off by even the smallest amount of the food or food component in question.

While fish, shellfish, peanuts and tree nuts cause most of the food allergies in adults, the foods most likely to trigger diarrhea are dairy, which can be especially difficult for people with an intolerance to lactose, fructose or artificial sweeteners.

When to See a Doctor About Diarrhea After Eating

The Cleveland Clinic recommends getting medical attention if you have severe diarrhea, especially with a fever lasting more than 24 hours, or if you're unable to drink or retain fluids because of vomiting.

"You should definitely see a doctor if you have any of those red-flag symptoms," Dr. Bulsiewicz says. "But I would add that any person whose diarrhea is affecting their quality of life has enough reason to see a doctor."