Food poisoning, also called foodborne illness, is caused by the ingestion of food that contains pathogenic bacteria or viruses. Symptoms of food poisoning can develop in as little as 30 minutes after eating the contaminated food and can last for several days. In most cases, you can avoid developing food poisoning by ensuring that food is stored at the appropriate temperature and cooked appropriately before eating.
Stomach Upset
The most immediate and common symptom that results from food poisoning is stomach upset. Symptoms of nausea, vomiting, diarrhea or abdominal pain reportedly occur less than an hour after exposure to contaminated food, as described in the "Bad Bug Book: Foodborne Pathogenic Microorganisms and Natural Toxins Handbook" published by the U.S. Food and Drug Administration. Even after the contaminated food has been expelled from your body you can still experience symptoms. Dry heaving---a condition in which you experience involuntary retching that does not produce vomit---will often develop due to food poisoning and can be painful and uncomfortable. Food poisoning that causes diarrhea can also lead to symptoms of abdominal cramping or bloating. Certain types of bacteria, such as V. vulnificus, can cause you to excrete blood or mucus within your stools. Gastronintestinal symptoms caused by bacteria or viruses typically persist for several days and can cause significant weight loss or dehydration.
Difficulty Breathing
If you ingest certain types of shellfish toxins (saxitoxins), you can develop respiratory paralysis within 30 minutes after consumption. Respiratory paralysis causes severe breathing difficulties and can lead to wheezing, coughing, dizziness, lightheadedness, double vision, fainting or loss of consciousness. In certain cases, these types of toxins can cause you to stop breathing. Other types of foodborne illnesses may cause you to collapse or can cause your skin color to appear blue---a condition called cyanosis that results from decreased oxygen within the blood. Such symptoms require immediate medical attention.
Fever
Eating food that has been contaminated with bacteria such as Salmonella or Escherichia coli (E. coli) can cause onset symptoms of fever to develop within two hours of exposure. The immune system of the body utilizes fever to prevent unwanted bacteria or viruses from multiplying and spreading throughout the body. A fever can also cause symptoms of headache, chills, sweating, muscle weakness or fatigue to develop.
