Nausea and vomiting in adults is not usually 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. 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.

This page provides more detailed advice on when to see your GP and covers some of the common causes of vomiting.

Motion sickness is covered in a separate topic.

When you should call your GP

Call your GP if you have any of the signs described 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.

Common causes of vomiting in adults

Gastroenteritis

Gastroenteritis or food poisoning are common causes of vomiting in adults.

Pregnancy

Pregnancy can cause vomiting. Pregnant women are especially likely to suffer nausea and vomit in the morning. Read more information about morning sickness.

Migraine

In migraine vomiting usually begins at the same time as the throbbing headache and disappears once the headache eases. Your GP will be able to prescribe anti-sickness medicine to help relieve this.

Appendicitis

Appendicitis, which is a medical emergency, can cause vomiting. You will also have extreme pain in your tummy and your appendix will need to be removed. You should dial 999 for an ambulance if you think you have appendicitis.

Labyrinthitis

Labyrinthitis is an inner ear infection that also causes dizziness and a feeling of spinning. Your GP will be able to prescribe medication to relieve your symptoms while your immune system fights off the infection, which may take a few weeks.

More unusual causes of vomiting in adults

The following can occasionally cause vomiting in adults:

• an abnormally high blood sugar level (hyperglycaemia) or low blood sugar level (hypoglycaemia)
• a blockage in your bowel, such as a hernia or gallstones
• a kidney infection
• a kidney stone that has blocked the tube from the kidney to the bladder through which urine passes
• certain medicines, such as antibiotics