How Long Does Stomach Flu Last?

It generally doesn't take long to get over the illness.

By

Anne Harding

and

Claire Gillespie

Updated on March 9, 2023

Medically reviewed by

Jay N. Yepuri, MD

Many viruses cause gastroenteritis, commonly known as stomach flu.
Depending on the type of virus, the length of your illness will vary but shouldn't last long. You should expect to start feeling like your usual self again within a few days.
If your symptoms don't go away or you have other health concerns, contact your healthcare provider.

The stomach flu is a common illness that goes by many names—including stomach bug and viral gastroenteritis, which is the medical name.

Most commonly, norovirus causes viral gastroenteritis. But other viruses, such as rotavirus (especially in children), adenovirus, sapovirus, and astrovirus, may also cause the illness.

Despite the name, the stomach flu doesn't have anything to do with influenza. But the illness can feel just as bad, or worse, than the flu. Between nausea, vomiting, diarrhea, and stomach cramps, if you've been there, you won't probably forget it.

Here's what you should know about how long viral gastroenteritis typically lasts in adults.

Stomach Flu Recovery Time

Viral gastroenteritis is a self-limiting disease. In other words, you'll recover on your own without treatment. With viral gastroenteritis, your immune system is busy trying to help you feel normal. Those types of diseases also resolve spontaneously.

Some people with viral gastroenteritis don't have any symptoms. But if you have symptoms and a healthy immune system, there's a good chance that they will go away rather quickly.

How Long Does Stomach Flu Last?

Typically, the timelines for viral gastroenteritis symptoms depend on the specific virus:

Norovirus: Generally, norovirus clears up within a couple of days.
Sapovirus: Usually, sapovirus lasts a few days. Although, diarrhea may continue for up to a week.
Astrovirus: This virus should resolve within two to three days.
Rotavirus: This virus can last anywhere from three to eight days.
Enteric adenoviruses: In some cases, enteric adenovirus can take up to two weeks to resolve.

You may need more time to recover if you have a weak immune system. People with weak immune systems may have a harder time fighting the virus than normal. Their symptoms may last longer than normal, and they also have a high risk for complications.

Conditions that may worsen your chances of a quick recovery include:

Immunodeficiency syndromes
Inflammatory bowel disease (IBD)
Structural heart disease
Metabolic diseases, such as diabetes
Kidney disease
Autoimmune conditions, like rheumatoid arthritis and lupus

Talk to a healthcare provider if you have any of those conditions and develop viral gastroenteritis.

When To Call a Healthcare Provider

Usually, diarrhea and vomiting are not causes for alarm. But if you see blood in your stool or vomit, call a healthcare provider right away. You should also seek help if you experience other signs of serious dehydration, including:

An extreme lack of energy
Confusion or otherwise altered mental state
A lack of urine or dark and concentrated urine

In addition, the Centers for Disease Control and Prevention (CDC) recommends seeking treatment for the following:

Your symptoms aren't getting better after three days.
You have prolonged vomiting that prevents you from drinking liquids.
Your temperature spikes above 102 degrees Fahrenheit.

Aside from severe dehydration, other reasons to get medical attention include:

Uncontrollable vomiting
Bloody diarrhea
Pregnancy

A healthcare provider may want to do lab tests to know what virus is causing your symptoms.

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Sources

Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

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