Diarrhoea And Vomiting



Vomiting in adults is usually not a sign of anything serious and tends to only last one or two days. Vomiting is the body’s way of ridding itself of harmful substances from the stomach, or it may be a reaction to something that has irritated the gut.

One of the most common causes of vomiting in adults is gastroenteritis. This is an infection of the gut usually caused by
bacteria or a virus, such as a norovirus (see video, left). Gastroenteritis also causes diarrhoea. Your immune system will
usually fight off the infection after a few days.

However, vomiting can occasionally be a sign of something more serious, such as a blockage in your bowel or kidney stones, so if you are feeling very unwell or are worried about your vomiting, trust your instincts and call your GP.


Looking after yourself

The most important thing you can do when vomiting is to keep taking small sips of fluid so you don’t become dehydrated. Drink water, squash, diluted fruit juice or semi-skimmed milk. A sweet drink can be useful for replacing lost sugar and a salty snack, such as a packet of crisps, can help replace lost salt. You may find that ginger helps to relieve your nausea and vomiting. Try drinking fresh ginger stewed in a mug of hot water.


When you should call your GP

Call your GP if you have any of the signs listed below, which mean you have a high risk of becoming dehydrated or may have a more serious underlying condition:

  • You have been vomiting uncontrollably for more than 24 hours.
  • You have not been able to keep down fluids for 12 hours or more.
  • Your vomit is green. In this case you are probably bringing up bile, a fluid the digestive system uses to digest foods. This suggests you may have a blockage in your bowel (see below).
  • There is blood in your vomit or what looks like coffee granules. This is a sign of a peptic ulcer.
  • You also have severe stomach pain.

Diarrhoea is passing loose or watery faeces more than three times a day. It affects almost everyone from time to time and is usually nothing to worry about. A common cause in both children and adults is gastroenteritis, an infection of the bowel. Gastroenteritis may also be caused by:

  • a virus, such as a norovirus or rotavirus
  • bacteria, which is often found in contaminated food
  • a parasite

Bouts of diarrhoea in adults may also be brought on by anxiety or drinking too much coffee or alcohol. Diarrhoea may also be a side effect of a medication.



In adults, diarrhoea caused by gastroenteritis will usually clear up in two to four days when the infection has cleared.

Taking antidiarrhoeal medicine is usually not necessary unless it is important that you shorten the length of time your diarrhoea lasts (for example, if you need to take a long-haul flight). Children should not take this medicine.

Diarrhoea in children usually passes within five to seven days, and will usually clear within two weeks. Seek medical advice if your child has diarrhoea for longer than this.


When to see your doctor



Contact your GP or health visitor urgently for advice if your baby has had six or more episodes of diarrhoea in the past 24 hours.



Contact your GP if your child has:

  • had six or more episodes of diarrhoea in the past 24 hours
  • diarrhoea and is vomiting at the same time
  • diarrhoea that is particularly watery
  • diarrhoea that has blood in it
  • diarrhoea that lasts for longer than two weeks


Contact your GP if you have:

  • recently been treated in hospital
  • recently been treated with antibiotics
  • diarrhoea that has blood in it
  • diarrhoea and persistent vomiting
  • unexplained weight loss
  • bleeding from your rectum (back passage)
  • passed large volumes of very watery diarrhoea – you may be at risk of dehydration (see below)
  • symptoms at night that are disturbing your sleep
  • diarrhoea that lasts longer than a week

Symptoms of dehydration

If diarrhoea is severe or persistent, it can cause dehydration.

Symptoms of dehydration in children include:

  • appearing to get more unwell
  • being irritable or drowsy
  • passing urine infrequently
  • pale or mottled skin
  • cold hands and feet

Dehydration in adults

Symptoms of dehydration in adults include:

  • lacking energy or feeling tired
  • loss of appetite
  • nausea
  • feeling light-headed
  • dizziness, especially when standing up
  • dry tongue
  • sunken eyes
  • muscle cramps
  • rapid heartbeat