Viral Gastroenteritis (Adult)

Gastroenteritis is often called the stomach flu. But it has nothing to do with influenza. It's most often caused by a virus that affects the stomach and intestinal tract. Most bouts last from 2 to 7 days. Common viruses causing gastroenteritis include norovirus, rotavirus, and hepatitis A. Nonviral causes of gastroenteritis include bacteria, parasites, and toxins.

The danger from repeated vomiting or diarrhea is dehydration. This is when the body loses too much fluid. When this occurs, you must replace the body fluids.

Antibiotics aren't an effective treatment for this condition because it's caused by a virus.

Symptoms of viral gastroenteritis may include:

  • Watery, loose stools

  • Stomach pain or belly (abdominal) cramps

  • Fever and chills

  • Nausea and vomiting

  • Loss of bowel control

  • Headache

Home care

Gastroenteritis is spread by contact with the stool or vomit of an infected person. This can occur from person to person or from contact with a contaminated surface.

Follow these guidelines when caring for yourself at home:

  • If symptoms are severe, rest at home for the next 24 hours or until you are feeling better.

  • Wash your hands with soap and clean, running water or use alcohol-based sanitizer to prevent the spread of infection. Wash your hands after touching anyone who is sick.

  • Wash your hands or use alcohol-based sanitizer after using the toilet and before meals. Clean the toilet after each use.

Remember these tips when preparing food:

  • People with diarrhea should not prepare or serve food to others. When preparing foods, wash your hands before and after.

  • Wash your hands after using cutting boards, counter tops, knives, or utensils that have been in contact with raw food.

  • Dry your hands with a single-use disposable towel.

  • Keep uncooked meats away from cooked and ready-to-eat foods.


Use acetaminophen or nonsteroidal anti-inflammatory drugs (NSAID) such as ibuprofen or naproxen to control fever, unless another medicine was given. If you have chronic liver or kidney disease, talk with your healthcare provider before using these medicines. Also talk with your provider if you've had a stomach ulcer or gastrointestinal bleeding. Don't give aspirin to anyone under 18 years of age who is ill with a fever. It may result in a serious illness called Reye syndrome that may cause severe liver damage or even death. Don't use NSAIDS if you're already taking one for another condition (like arthritis) or are on aspirin (such as for heart disease or after a stroke).

If medicines for vomiting or diarrhea are prescribed, take these only as directed. Nausea and diarrhea medicines are generally OK unless you have bleeding, fever, or severe abdominal pain.


Follow these guidelines for food:

  • Water and liquids are important so you don't get dehydrated. Drink small amounts often or suck on ice chips as tolerated if you are vomiting.

  • If you eat, stay away from fatty, greasy, spicy, or fried foods.

  • Don't eat dairy if you have diarrhea. This can make diarrhea worse.

  • Avoid tobacco, alcohol, and caffeine. These may worsen symptoms.

During the first 24 hours (the first full day), follow the diet below:

  • Beverages. Sip sports drinks, soft drinks without caffeine, ginger ale, mineral water (plain or flavored), decaffeinated tea and coffee. If you are very dehydrated, sports drinks aren't a good choice. They have too much sugar and not enough electrolytes. In this case, use products called oral rehydration solutions. You can buy these at pharmacies and grocery stores.

  • Soups. Eat clear broth, consommé, and bouillon.

  • Desserts. Eat gelatin, ice pops, and fruit juice bars.

During the next 24 hours (the second day), you may add the following to the above:

  • Hot cereal, plain toast, bread, rolls, and crackers

  • Plain noodles, rice, mashed potatoes, chicken noodle or rice soup

  • Unsweetened canned fruit (avoid pineapple), bananas

  • Limit fat intake to less than 15 grams per day. Do this by avoiding margarine, butter, oils, mayonnaise, sauces, gravies, fried foods, peanut butter, meat, poultry, and fish.

  • Limit fiber and avoid raw or cooked vegetables, fresh fruits (except bananas), and bran cereals.

  • Limit caffeine and chocolate. Don't use spices or seasonings other than salt.

  • Limit dairy products.

  • Avoid alcohol.

During the next 24 hours:

  • Gradually resume a normal diet as you feel better and your symptoms improve.

  • If at any time it starts getting worse again, go back to clear liquids until you feel better.

Follow-up care

Follow up with your healthcare provider, or as advised. Call your provider if you don't get better within 24 hours or if diarrhea lasts more than a few days. It's also important to follow up if you can't keep down liquids, which can lead to becoming dehydrated. If a stool (diarrhea) sample was taken, call as directed for the results.

Call 911

Call 911 if any of these occur:

  • Trouble breathing

  • Chest pain

  • Confused

  • Severe drowsiness or trouble awakening

  • Fainting or loss of consciousness

  • Rapid heart rate

  • Seizure

  • Stiff neck

When to get medical advice

Call your healthcare provider right away if any of these occur:

  • Abdominal pain that gets worse

  • Continued vomiting (can't keep liquids down)

  • Frequent diarrhea (more than 5 times a day)

  • Blood in vomit or stool (black or red color)

  • Dark urine, reduced urine output, or extreme thirst

  • Weakness or dizziness

  • Drowsiness

  • Fever of 100.4°F (38°C) or higher, or as advised by your provider

  • New rash

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