8.FEB.2019 3 MIN READ | 3 MIN READ

Gastroenteritis is a medical condition characterised by inflammation in your stomach and intestines.

If you experience a period of feeling unwell, when you're unable to keep your food down and you spend all day in the bathroom, chances are you've got gastroenteritis.

Read on for everything you need to know about the pesky condition also known as the ‘stomach flu’.

Symptoms of gastroenteritis

Most people experience gastroenteritis at some stage of their lives, so you've probably already had some of the following symptoms:

  • Watery diarrhoea
  • Nausea
  • Vomiting
  • Stomach pain and cramps
  • Fever
  • Headache

In rare cases, gastroenteritis can leave you severely dehydrated. Watch out for:

  • Intense thirst
  • Sunken eyes
  • Dizziness
  • Feeling foggy or unable to focus
  • Blurred vision
  • Dry mouth

If you experience these symptoms, visit the emergency department or call an ambulance. You should also seek help if:

  • Your vomiting lasts more than a day
  • Your diarrhoea lasts more than 2 days
  • You have a chronic illness, such as diabetes, kidney disease or heart problems
  • You notice blood in your vomit or stools
  • You experience severe abdominal pain
  • Fever of more than 38°C
  • Pregnant

Gastroenteritis in infants and young children

Children and infants are at particular risk of severe symptoms from gastroenteritis. Because they become dehydrated much faster than adults, keep a close eye on them if they are unwell. If you notice a sunken fontanelle (the soft spot on the top of their skull), extreme thirst, fewer or no wet nappies, dry skin, or severe irritability or lethargy, take them to the emergency room. If in doubt, seek medical attention.

Although gastroenteritis is not fully preventable, there are vaccinations available for some of the viral infections that cause it, such as rotavirus, which you should ask your doctor about.

Causes of gastroenteritis

Gastroenteritis is usually caused by a virus such as rotavirus or norovirus. Norovirus is the most common cause of acute gastroenteritis worldwide, accounting for 685 million cases a year. Other viral infections leading to gastro include astrovirus and adenovirus.

Viral infections are easily spread which is why outbreaks of gastroenteritis are so frequent. These viruses are often transmitted because of:

  • Person to person contact
  • Water or food that is contaminated
  • Failure to keep surfaces clean
  • Poor hand-washing techniques
  • Being in cramped or close quarters with infected people

Gastroenteritis vs food poisoning

Gastroenteritis is the inflammation of the stomach or the intestine. If the gastroenteritis is caused by contaminated food it is then labelled as food poisoning. Food poisoning can be caused by food contaminated with bacteria, viruses or parasites. Most people find they contract food poisoning from the following:

  • Raw eggs or meat
  • Unpasteurised soft cheese or milk
  • Raw fish or shellfish
  • Leftover rice that was not reheated adequately
  • Unwashed fruit or vegetables

The symptoms are the same as gastroenteritis. The onset of symptoms from eating the contaminated food varies, depending on the contaminant which can range from 1 hour – 7 days.

Preventing gastroenteritis

  • Wash your hands before cooking or handling food
  • Sanitise surfaces, such as your kitchen counter or work desk, regularly
  • Keep raw foods separate from ready-to-eat foods
  • Avoid raw or undercooked food
  • Refrigerate and freeze perishable food promptly
  • Talk to your doctor about vaccinations for your child

Managing and treating gastroenteritis

In most cases, gastroenteritis will resolve itself on its own. If the symptoms persist, or are severe, you may need a course of antibiotics. However, if the symptoms are mild, you can try the following:

  • Increase your fluid intake. Do not drink too much at once in case it triggers vomiting. Try to take in a cup of water every hour. Young children should have a smaller amount every 30 minutes. Frozen ice popsicles are another way to encourage your child to take in fluid if they aren’t getting enough.
  • Encourage rehydration with electrolytes. Oral rehydration solutions can be dissolved in your water, or you can try sports drinks, which can help to replenish what your body has lost. Try to avoid sugary drinks if you can. Your doctor can advise what might be best for you and can offer you infant solutions if you have young children.
  • Eat easily digestible foods. As you start to be able to keep food down, choose foods such as rice, potatoes, toast, and bananas. This will allow you to recover some energy without disrupting your stomach. As you start to feel better, reintroduce food as part of your usual balanced diet. Avoid alcohol, caffeine, and foods high in sugar or fat.
  • Get plenty of rest.

If the symptoms persist, or if in doubt, speak to a doctor or visit the accident & emergency department for immediate medical attention.


Article reviewed by Dr Vincent Lai, gastroenterologist at Gleneagles Hospital

Lai Wai Kwan Vincent
Gleneagles Hospital

Dr Vincent Lai is a gastroenterologist practising at Gleneagles Hospital, Singapore. His clinical interests include liver failure, viral hepatitis (liver inflammation) and liver transplantation. He is trained in therapeutic endoscopy and endoscopic retrograde cholangiopancreatography (ERCP), whereby imaging of internal organs aid the treatment of gastrointestinal and liver conditions.