Vomiting
Vomiting is forceful expulsion of stomach contents and can result from gut infection, obstruction, migraine, pregnancy, medicines, toxins, vestibular disease or brain and metabolic disorders.
Key points
- Hydration status, age, pregnancy, pain, neurological symptoms and duration matter more than vomiting frequency alone.
- Small frequent amounts of oral rehydration may help mild illness, but ongoing losses can disturb salts and kidney function.
- Antiemetics target particular pathways and can mask deterioration, prolong QT or cause movement and other adverse effects.
Catalogue matches do not identify the cause of vomiting or indicate a safe antiemetic and dose.
What clues point to the cause?
Diarrhoea and sick contacts suggest infection, while abdominal swelling or inability to pass stool raises obstruction concern. Morning vomiting may have several causes; pregnancy testing, medicine review and neurological assessment are used where relevant.
How are antiemetics selected?
Metoclopramide, domperidone and prochlorperazine are not interchangeable. Heart rhythm, Parkinsonism, bowel obstruction, age and interactions affect suitability; see digestive health.
When to seek urgent care
Seek urgent care for vomiting blood or green fluid, severe abdominal pain or swelling, stiff neck, severe headache, confusion, head injury, very low urine, fainting or inability to keep fluids down.