When to worry about vomiting with gastroenteritis

Gastroenteritis inflames the stomach and bowel, often causing vomiting, watery diarrhoea, cramps, nausea, and sometimes fever. Vomiting and diarrhoea together can remove fluids and salts quickly. Watch for dry mouth, thirst, dark urine, reduced urination, dizziness, weakness, or sleepiness.

Most mild illness can be supported at home, but the pattern matters. Blood in vomit or stool, green vomit, severe or focused abdominal pain, a swollen abdomen, or worsening fever needs clinical assessment rather than self-care alone.

Rest, wash your hands often, and take small sips of water or oral rehydration fluid. If a drink triggers vomiting, wait briefly and restart with slower, smaller sips. Eat plain foods when ready and avoid alcohol and heavy meals until symptoms settle. Stay home from work or school while actively vomiting and follow local advice about returning.

Arrange prompt medical care if vomiting continues and you cannot replace fluids, you are passing very little urine, or you feel faint, unusually drowsy, or confused. Seek urgent help for blood, severe abdominal pain, breathing difficulty, or rapidly worsening symptoms. Children, older adults, pregnant people, and those with chronic illness may need advice earlier.

What is the safest fluid plan for me? How can I recognise dehydration? Do my medicines need adjustment while I am vomiting? At what point should ongoing diarrhoea, fever, or abdominal pain be checked?