What is vomiting?

Vomiting is a symptom, not a condition. It’s a reflex that helps your body get rid of harmful substances. When you vomit, your abdominal muscles have strong contractions pushing out the contents of your stomach.

Seek immediate medical attention if you are vomiting and:

• have a fever (high temperature)
• have signs of dehydration
• can't keep water down

Vomiting may be a short-term or long-term problem.

There are many different reasons that you could be vomiting. The most common cause of acute (short-term) vomiting is viral gastroenteritis (gastro, stomach bug or stomach flu).

If you have recurrent or chronic (long-term) vomiting that continues for more than 2 days, see your doctor.

For information on the underlying causes of vomiting in children 12 years and under, see vomiting in children.

What causes acute vomiting?

Acute (short-term) vomiting may be caused by an infection, a medical treatment, poisoning, or some other reason.

Gastroenteritis

An infection of the digestive tract is one of the most common causes of nausea and sudden vomiting.

Gastroenteritis is often caused by a virus, such as norovirus or rotavirus.

Bacteria such as Salmonella, Shigella or Campylobacter, can also cause gastroenteritis. These bacteria are associated with ‘food poisoning’.

Diarrhoea and abdominal pain often happen along with vomiting.

Food poisoning

Some bacteria can cause food poisoning due to toxins (poisons) that they release into food.

Bacillus cereus and staphylococcus aureus are examples of bacteria that can cause food poisoning. Symptoms of vomiting can start soon after eating the contaminated food.

Poisoning

Many household items are poisonous if swallowed. Symptoms of poisoning include:

• nausea and vomiting
• drowsiness
• seizures
• breathing difficulties

Do NOT attempt to make yourself vomit, unless told to do so by a doctor.

Motion sickness

Motion sickness can cause vomiting in adults. You may also go pale and have cold sweats.

Too much alcohol

Drinking too much alcohol can often cause nausea and vomiting, or even alcohol poisoning.

After surgery

If you have just had surgery, you are likely to feel nauseous or vomit. You might be given anti-emetic medicines to stop you vomiting.

Gastrointestinal obstruction

An obstruction in your digestive tract will cause vomiting. It often begins without nausea.

Depending on where the blockage is, you may vomit:

• bile
• faecal material
• partly digested food

Seek urgent medical help if you have symptoms of bowel obstruction.

Appendicitis

Appendicitis can cause both nausea and vomiting. Appendicitis usually causes a dull pain that starts around the navel (belly button). Pain might travel to the lower right of the abdomen and start to feel sharp. Other symptoms of appendicitis are a loss of appetite, fever or chills.

If appendicitis is not treated your appendix can become swollen and infected. It can even burst. Urgent surgery is the usual treatment for appendicitis.

Pancreatitis

Pancreatitis is inflammation of your pancreas. It usually causes:

• abdominal pain
• vomiting
• fever

It can be very severe, even life-threatening.

Raised intracranial pressure

Raised pressure in your skull is a medical emergency and can cause nausea and vomiting.

It might be due to:

• a head injury
• meningitis
• a tumour

Your vomiting may be worse in the morning and may be projectile.

Meningitis

Symptoms of meningitis can happen suddenly, and include:

• vomiting
• fever
• headache
• a stiff neck
• photophobia (light sensitivity)
• a distinctive rash

COVID-19

Nausea, diarrhoea and vomiting can all be symptoms of COVID-19.

Diabetic ketoacidosis

If you have diabetes, vomiting can be a symptom of diabetic ketoacidosis. This is a medical emergency and can be fatal.

It happens when your blood sugar level is very high and you don’t have enough insulin in your body.

What causes chronic (long term) vomiting?

Vomiting can be a symptom of a chronic (ongoing) health problem. If vomiting continues for longer than a few days, see your doctor.

Medicines

Nausea or vomiting can be a side effect of many medicines. Examples of medicines that can cause vomiting are:

• non-steroidal anti-inflammatory medicines (NSAIDs)
• nicotine patches
• anti-arrhythmic (medicines that suppress abnormal heart rhythms)
• metformin (a diabetes medicine)
• some antibiotics
• anticonvulsants

To find out about your medicine, you can talk to your pharmacist or read the consumer medicine information. Sometimes it is included in the pack, or you can search for it..

If you suspect that a medicine is causing vomiting, speak to your doctor or pharmacist. They can advise you and may be able to substitute it with another medicine.

Substance abuse can also cause vomiting.

LOOKING FOR A MEDICINE? — To search by brand name or active ingredient, use the Medicines information search feature.

Chemotherapy medicines

Nausea and vomiting can be a side effect of chemotherapy. These symptoms usually start a few hours after treatment.

Tell your nurse or doctor if you feel sick. They may be able to give you medicine to stop the vomiting (antiemetic medicines).

Radiation treatments

Nausea or vomiting can be a side effect of radiotherapy. If you suffer from nausea or vomiting after treatments, tell the radiation oncologist or nurse.

They may be able to give you antiemetic medicines to stop your symptoms.

Vitamins

High doses of some vitamins can cause vomiting. Remember to tell your doctor or pharmacist about everything you are taking, including herbs, vitamins and other complementary medicines.

Pregnancy

Morning sickness is common during early pregnancy. It involves nausea and vomiting at any time of the day, but often in the morning.

Usually, your symptoms will improve after the first 3 months of pregnancy. Hyperemesis gravidarum is a more serious level of vomiting during pregnancy.

Migraine

Nausea and vomiting are common symptoms of a migraine. You might vomit in the headache phase, after the aura — if you have one.

Food allergies

Food allergies can cause ongoing digestive symptoms including:

• vomiting
• diarrhoea
• constipation
• flatulence (wind)
• bloating

If you have symptoms shortly after eating see your doctor or a dietitian for advice.

Upper digestive tract disorders

If you often vomit after meals, this could be caused by gastro-oesophageal reflux disease GORD.

Gastroparesis

Gastroparesis is a delayed emptying of the stomach due to nerve damage. It can lead to nausea and vomiting after meals.

Kidney stones

Nausea and vomiting are symptoms of kidney stones, along with gripping pain in your back.

Functional nausea and vomiting

Functional nausea and vomiting is the name given to chronic nausea and vomiting when there is no clear medical cause.

Cyclic vomiting syndrome is a rare syndrome that is a type of functional nausea and vomiting.

Resources and support

To learn more about long term causes of digestive problems, try this resource The Gut Foundation.

If you need to speak to someone about vomiting, call healthdirect on 1800 022 222 to speak with a registered nurse, 24 hours, 7 days a week.

FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.