What causes vomiting?

Gastroenteritis and food poisoning often cause vomiting with nausea, cramps, diarrhoea, or fever. Rotavirus infection is one infectious cause, especially in young children. Pancreatitis and gallstones can cause vomiting with significant upper abdominal pain. Heat stroke can cause vomiting alongside hot skin, confusion, faintness, or a very high body temperature.

Other triggers include motion sickness, migraine, alcohol, medication side effects, and pregnancy. The timing, associated pain, bowel symptoms, fever, recent food, travel, and fluid intake help a clinician narrow the possibilities. Vomiting itself can lead to dehydration, particularly when fluids cannot be kept down.

Take small, frequent sips of water or an oral rehydration drink. After vomiting settles, try bland foods in small amounts and avoid alcohol and heavy meals for a while. Wash hands carefully if an infection is possible. Do not give anti-vomiting medicines to a child unless a clinician or pharmacist recommends them. Keep track of urine, alertness, pain, and whether fluids stay down.

Get urgent medical help for blood or coffee-ground material in vomit, severe or worsening abdominal pain, a stiff neck, confusion, fainting, breathing difficulty, or suspected heat stroke. Seek prompt care if vomiting follows a head injury, continues so that fluids cannot stay down, or occurs in a baby, older adult, or person with a serious medical condition. Reduced urination, a dry mouth, dizziness, and unusual sleepiness can signal dehydration.

Tell the clinician when vomiting began, how often it occurs, what it looks like, and whether pain, fever, diarrhoea, headache, pregnancy, travel, or a new medicine is involved. Ask whether you need hydration treatment, tests, or advice about your regular medicines.