Patient education: Viral gastroenteritis in adults (The Basics)

What is viral gastroenteritis? — Viral gastroenteritis is an infection that can cause diarrhea and vomiting. It happens when a person's stomach and intestines get infected with a virus (figure 1).

People can get the infection if they:

●Touch an infected person or a surface with the virus on it, and then don't wash their hands

●Eat foods or drink liquids with the virus in them. If people with the virus don't wash their hands, they can spread it to food or liquids they touch.

What are the symptoms of viral gastroenteritis? — The infection causes diarrhea and vomiting. People can have either diarrhea or vomiting, or both. These symptoms usually start suddenly, and can be severe.

Viral gastroenteritis can also cause:

●Fever

●Headache or muscle aches

●Belly pain or cramping

●Loss of appetite

If you have a lot of diarrhea and vomiting, your body can lose too much water. This is known as "dehydration." Dehydration can make you feel thirsty, tired, dizzy, or even confused. It can also make your urine look dark yellow.

Severe dehydration can be life-threatening. Older people are more likely to get severe dehydration.

Will I need tests? — Not usually. Your doctor or nurse should be able to tell if you have viral gastroenteritis by learning about your symptoms and doing an exam. But the doctor or nurse might do tests to check for dehydration or to see which virus is causing the infection. These tests can include:

●Blood tests

●Urine tests

●Tests on a sample of bowel movement

Is there anything I can do on my own to feel better? — Yes. You need to replace the body's fluids that are lost through vomiting and diarrhea:

●Drink fluids when you are able. It might help to take small sips every 15 to 30 minutes. Try to drink more as you start to feel better.

●When you have a lot of vomiting or diarrhea, your body loses both water and salt. Drinking fluids that contain some salt can help replace what your body has lost. Examples include "oral rehydration solutions," sports drinks, and broth. If you drink a lot of plain water, make sure you are also eating. This will help your body keep the right salt and water balance.

●Avoid drinks with a lot of sugar, like juice or soda. Avoid alcohol, too.

●Eat when you are able. If you can keep food down, it's best to eat lean meats, fruits, vegetables, and whole-grain breads and cereals. Avoid eating foods with a lot of fat or sugar, which can make symptoms worse.

If you are an adult younger than 65 and you have a new bout of diarrhea, and no fever and no blood in your bowel movements, you can take medicine to stop diarrhea such as loperamide (brand name: Imodium) for 1 to 2 days. But if you are older than 65, have a fever, or have blood in your bowel movements, do not take these medicines without checking with your doctor.

If you have diabetes, you might need to check your blood sugar more often until you feel better. Ask your doctor or nurse about this.

Should I call the doctor or nurse? — Call the doctor or nurse if you:

●Have any symptoms of dehydration, like feeling very tired, thirsty, dizzy, or confused

●Have diarrhea or vomiting that lasts longer than a few days

●Vomit up blood, have bloody diarrhea, or have severe belly pain

●Haven't been able to drink anything for many hours

●Haven't needed to urinate in the past 6 to 8 hours (during the day)

How is viral gastroenteritis treated? — Most people do not need any treatment, because their symptoms will get better on their own. But people with severe dehydration might need treatment in the hospital. This involves getting fluids through a thin tube that goes into a vein, called an "IV."

Doctors do not treat viral gastroenteritis with antibiotics. That's because antibiotics treat infections that are caused by bacteria, not viruses.

Can viral gastroenteritis be prevented? — Sometimes. To lower the chance of getting or spreading the infection, you should wash your hands well with soap and water:

●After you use the bathroom

●Before you eat

●Before you prepare food

Also, if you are caring for a child in diapers, make sure you wash your hands well after changing diapers. Do not change diapers near where you cook or eat food.

More on this topic

Patient education: Dehydration in children (The Basics)
Patient education: Diarrhea in adolescents and adults (The Basics)
Patient education: Diarrhea in children (The Basics)
Patient education: Nausea and vomiting in adults (The Basics)
Patient education: Food poisoning (The Basics)
Patient education: Vaccines for babies and children age 0 to 6 years (The Basics)
Patient education: Rotavirus infection (The Basics)

Patient education: Acute diarrhea in adults (Beyond the Basics)
Patient education: Acute diarrhea in children (Beyond the Basics)
Patient education: Nausea and vomiting in infants and children (Beyond the Basics)
Patient education: Foodborne illness (food poisoning) (Beyond the Basics)