January 7, 2020/Digestive

What to Do When Your Stomach Bug Won’t Go Away

You might have a condition called “post-infectious IBS”

illustration of woman suffering from stomach bugs

If you’ve battled a gastrointestinal (GI) infection before, you know it’s not pleasant. But typically symptoms don’t last longer than a few days.


Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

However, in some cases, the effects linger for weeks or months — even after a person is no longer vomiting or having severe symptoms after a bad bout with a virus or food poisoning. Some patients just can’t seem to get back to a normal GI rhythm or bowel function.

This condition is known as post-infectious irritable bowel syndrome (IBS). Gastroenterologist Brian Kirsh, MD, says post-infectious IBS is fairly common — and you can take steps to diagnose and treat it.

What symptoms to watch for

“Post-infectious IBS is a constellation of symptoms that resemble irritable bowel syndrome,” Dr. Kirsh says.

Symptoms are usually less severe than the original infection and may include:

  • Abdominal cramping.
  • Diarrhea.
  • Nausea.
  • In some cases, constipation.

“Over time people do tend to get better,” he says. “For most of them, this is not going to be lifelong IBS.”

The symptoms of post-infectious IBS develop after an infectious GI bug such as viral gastroenteritis or a bacterial infection like E. coli or Salmonella or even C. difficile. Patients may suspect this condition if they had a documented GI infection that resolved, but their digestive function won’t go back to normal. “That should tip them off that they should seek out help.”

How long post-infectious IBS lasts

Symptoms last for weeks, months or sometimes even a year. Why it tends to linger is unclear, Dr. Kirsh says.


“I’m not sure anyone can answer that,” he says. “There are things we just don’t know about why certain things cause irritability to certain parts of the body.”

One theory suggests that the original GI infection results in some change in a person’s normal bacterial count in their small bowel. “That may have some lingering impact on symptoms.”

What you eat matters

Altering your diet can help relieve symptoms of post-infectious IBS. But keep in mind dietary remedies vary by patient.

For example, some people may find benefits from limiting wheat products. Others may need to stop eating dairy.

Research has shown that a low-FODMAP diet works well for most IBS symptoms. The diet recommends eliminating certain sugars that are difficult to digest. For example, a person on a low-FODMAP diet would avoid fruits such as apples, apricots, cherries and pears. Instead, they’d eat fruits like bananas, grapes and cantaloupe.

Overall, though, there’s no one-diet solution for everyone. So work with your doctor to find the best option for you.

Supplements and medications may help

If you have post-infectious IBS, your doctor may recommend probiotics. These supplements help repopulate the small intestine with healthy flora, Dr. Kirsh says.


A doctor might also prescribe antispasmodics or recommend antidiarrheal medications, many of which are available over the counter.

When testing is beneficial

Depending on the severity of the case, a doctor might order a blood test. This test can help make sure a person with post-infectious IBS isn’t anemic and doesn’t have an elevated white blood cell count. Patients may also get their electrolytes tested to make sure they’re not dehydrated.

Depending on your symptoms, some patients may undergo further testing for celiac disease or receive an endoscopy or colonoscopy, too.

Most people recover

Provided you don’t have a chronic condition such as ulcerative colitis or Crohn’s disease, take this to heart: Post-infectious IBS shouldn’t last forever.

“Over time people do tend to get better,” Dr. Kirsh says. “For most of them, this is not going to be lifelong IBS.”

Learn more about our editorial process.

Related Articles

Teacup of tea and plate of toast
February 2, 2024/Primary Care
What To Eat, Drink and Avoid When You Have the Stomach Flu

Start slowly with clear fluids, and then move to bland, easy-to-digest foods

Person sick to stomach and by bathroom toilet to vomit.
Stomach Flu or Food Poisoning? How To Tell

Time of onset and duration of symptoms tell the story

man sick wants to vomit
April 4, 2022/Digestive
Vomiting 101: Why You Throw Up and the Best Way To Recover

Drink small amounts of water for a few hours after throwing up

Bananas Rice Applesauce Toast BRAT diet
November 25, 2021/Digestive
When Should You Follow the BRAT Diet?

If you’ve got a stomach bug, bananas, rice, applesauce and toast are easy on your stomach

woman in bathroom sick on floor
March 7, 2021/Digestive
Do You Know When to Visit the Hospital for Vomiting?

How to treat vomiting at home and when to see a doctor

woman with stomach cramping
5 Simple Tips to Prevent Norovirus This Winter

Start with common sense — and wash your hands

Colonscopy exam showing light inside colon
March 15, 2024/Digestive
How Safe Are Colonoscopies?

They might not be fun, but colonoscopies are low-risk, high-reward procedures

Female and male waking up with hangovers in aftermath of a party
March 13, 2024/Digestive
Hangover Pills Aren’t Worth the Hype

Misleading claims, lack of scientific evidence and the risk of over-doing it are all concerns

Trending Topics

Person in yellow tshirt and blue jeans relaxing on green couch in living room reading texts on their phone.
Here’s How Many Calories You Naturally Burn in a Day

Your metabolism may torch 1,300 to 2,000 calories daily with no activity

woman snacking on raisins and nuts
52 Foods High In Iron

Pump up your iron intake with foods like tuna, tofu and turkey