When does food poisoning start?

The delay depends on what contaminated the food, how much was consumed, and how the body responds. Some toxins irritate the gut quickly; infections may take longer while organisms multiply or trigger inflammation. Nausea, vomiting, watery diarrhoea, abdominal pain, and fever can appear in different combinations. The last meal is not always the source, because symptoms can begin after an earlier exposure.

Write down when you ate, when symptoms began, and whether anyone sharing the meal is unwell. Keep packaging or food details if they are available, but do not eat food you suspect is unsafe.

Begin replacing fluids as soon as symptoms start. Take regular small sips of water or oral rehydration solution, then add simple foods as tolerated. Rest and wash hands with soap and water after using the bathroom. Avoid preparing meals for others while vomiting or having diarrhoea. Do not use onset timing to decide that symptoms are harmless; monitor hydration and the overall pattern instead.

Seek urgent assessment for severe or worsening abdominal pain, blood in vomit or stool, confusion, fainting, breathing difficulty, or inability to keep fluids down. Reduced urine and pronounced dizziness suggest dehydration. Contact a clinician sooner for a baby, older adult, pregnant person, or someone with a weakened immune system. A healthcare professional can decide whether IV Fluid Therapy or other care is appropriate.

Does the timing fit any particular type of illness? What details about meals or contacts should I record? Which changes mean I need same-day care?