Symptoms of Food Poisoning

Symptoms usually start a few hours to a few days after eating contaminated food. Most people recover within one to three days.

Common symptoms

• Nausea and vomiting
• Watery diarrhoea
• Stomach cramps and pain
• Loss of appetite
• Low-grade fever and chills
• Headache, weakness and body aches

Timing clues

• Within 1 to 6 hours: often a toxin, such as from Staphylococcus aureus or Bacillus cereus. Vomiting is prominent.
• 8 to 72 hours: usually Salmonella, norovirus, E. coli and similar infections.
• Days to weeks: parasites, hepatitis A or Listeria.

Signs of dehydration

• Very dry mouth and thirst
• Passing little or no urine for 8 hours or more
• Dizziness or fainting
• Sunken eyes
• Very sleepy or weak, or a baby with a sunken soft spot

See a doctor the same day if

• Blood in stool or black stools
• High fever above about 39 degrees C (102 F)
• Diarrhoea lasting more than three days
• Severe or worsening abdominal pain
• Vomiting that stops you keeping any fluids down
• Signs of dehydration
• Pregnancy, young infants, older age or weak immunity
• Blurred vision, double vision, muscle weakness or difficulty swallowing (possible botulism)
• Suspected mushroom or seafood poisoning

For emergencies, call 112 or 102.

Not always food poisoning

Viral infections, appendicitis and other conditions can look similar. If the picture is unclear or worsening, get examined.

In children

Children can become dehydrated faster than adults. Watch for fewer wet nappies, no tears when crying, unusual sleepiness and refusing to drink, and seek medical advice early.