Food poisoning is characterized by abdominal pain, with or without diarrhea, vomiting, sweating, and/or weakness. It usually occurs within 24-96 hours of eating food contaminated with a virus or bacteria.
Symptoms of food poisoning vary greatly. Symptoms can manifest as quickly as 30 minutes to one hour if due to chemical food poisoning; one to twelve hours in cases due to bacterial poisoning; 12 to 48 hours in cases due to viral or salmonella poisoning. Symptoms can range from stomach pain and nausea to constipation, diarrhea (sometimes in alternation with each other) and, in very severe cases, collapse and shock.
Food poisoning is far more common than is typically believed. Many cases of diarrhea each year, for instance, are due to food poisoning. Many of these cases go unreported as the cause is not known and is usually attributed to the stomach flu.
Flu, gastrointestinal disorders, digestive enzyme deficiencies, drug interactions, stress, and nutrient deficiencies or excess (too much magnesium can cause loose stools and abdominal cramps) can all mimic symptoms of food poisoning. In infants, symptoms can also be due to an intolerance to honey.
You should suspect food poisoning if a number of people who ate the same food have come down with similar symptoms.
Types: The most common forms of food poisoning are food that contains salmonella, found in farm animals or passed on by improper food handling or flies from contaminated fecal material; frozen poultry that is not completely thawed before being cooked; contaminated drinking water; foods that remain at room temperature too long, which can encourage Clostridium - often referred to as the "cafeteria germ" to grow; and food products such as chicken, duck, or geese, raw or partly cooked eggs, or raw fish such as clams, oysters, or sushi.
Other causes include organisms such as Staphylococcal bacteria, which can be passed through the hands, coughing, sneezing, or breathing onto the food, botulism, which can occur in food preserved at home; viruses that contaminate shellfish due to contaminated waters; and other infective organisms such as Giardia and Campylobacter, which can take up to one week before causing symptoms.
Noninfective food poisoning is another factor and is caused by poisonous mushrooms, toadstools, and fresh vegetables and fruits that have been contaminated with chemicals and insecticides, stored in inappropriate containers, or from leakage of metals from the containers into the food.
Note: If food poisoning is due to chemical or bacterial toxins, proper treatment may require pumping the stomach. Food poisoning usually improves within three days unless due to botulism, chemical poisoning, or mushroom poisoning. However, some infected organisms do not cause identifiable initial symptoms but can linger in the body and may cause long-term health problems that are difficult to diagnose.
Caution: In cases of food poisoning that cause severe vomiting and diarrhea, seek immediate emergency medical care and if possible, keep samples of food available for testing.