Food poisoning

Food poisoning, also called foodborne illness, is illness caused by eating contaminated food. Infectious organisms — including bacteria, viruses and parasites — or their toxins are the most common causes of food poisoning.

Infectious organisms or their toxins can contaminate food at any point of processing or production. Contamination can also occur at home if food is incorrectly handled or cooked.

Food poisoning symptoms, which can start within hours of eating contaminated food, often include nausea, vomiting or diarrhea. Most often, food poisoning is mild and resolves without treatment. But some people need to go to the hospital.

Symptoms Causes Risk factors Complications Prevention

Food poisoning symptoms vary with the source of contamination. Most types of food poisoning cause one or more of the following signs and symptoms:

  • Nausea
  • Vomiting
  • Watery diarrhea
  • Abdominal pain and cramps
  • Fever

Signs and symptoms may start within hours after eating the contaminated food, or they may begin days or even weeks later. Sickness caused by food poisoning generally lasts from a few hours to several days.

When to see a doctor

If you experience any of the following signs or symptoms, seek medical attention.

  • Frequent episodes of vomiting and inability to keep liquids down
  • Bloody vomit or stools
  • Diarrhea for more than three days
  • Extreme pain or severe abdominal cramping
  • An oral temperature higher than 101.5 F (38.6 C)
  • Signs or symptoms of dehydration — excessive thirst, dry mouth, little or no urination, severe weakness, dizziness, or lightheadedness
  • Neurological symptoms such as blurry vision, muscle weakness and tingling in the arms

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