Food poisoning most commonly causes:
This can cause significant amounts of fluid loss and diarrhea along with nausea and vomiting may make it difficult to replace lost fluid, leading to dehydration. In developing countries where infectious epidemics cause diarrheal illnesses, thousands of people die because of dehydration.
As noted in the section above, other organ systems may be infected and affected by food poisoning. Symptoms will depend upon what organ system is involved (for example, encephalopathy due to brain infection).
Most cases of food poisoning last about 1 to 2 days and symptoms resolve on their own. If symptoms persist longer than that, the affected person should contact their health-care professional.
Cyclospora infections may be difficult to detect and diarrhea may last for weeks. Health-care professionals may consider this parasite as the potential cause of food poisoning in patients with prolonged symptoms.
There many causes of food poisoning. Sometimes they are classified by how quickly the symptoms begin after eating potentially contaminated food. Think of this as the incubation time from when food enters the body until symptoms begin. The following are examples of how this time classification can be arranged:
Intermediate incubation from about 1 to 3 days
Infections of the large intestine or colon can cause bloody, mucousy diarrhea associated with crampy abdominal pain.
Diarrhea due to small bowel infection tends not to be bloody, but infections may affect both the small and large intestine at the same time.
Very long incubation of up to a month
Anyone can come down with food poisoning. Statistically speaking, nearly everyone will come down with food poisoning at least once in their lives.
There are some populations that are more at risk than others. Anyone with a suppressed immune system or an auto-immune disease may have a greater risk of infection and a greater risk of complications resulting from food poisoning.
If you have food poisoning, chances are it won’t go undetected. Symptoms can vary depending on the source of the infection. The length of time it takes for symptoms to appear also depends on the source of the infection, but it can range from as little as 1 hour to as long as 28 days. Common cases of food poisoning will typically include at least three of the following symptoms:
Symptoms of potentially life-threatening food poisoning include:
If you experience any of these symptoms, you should contact your doctor immediately.
Most times, the diagnosis of food poisoning is made by history and physical examination. Often, the patient volunteers the diagnosis when they come for medical care. For example, "I got sick after eating potato salad at a picnic," or, "I drank a raw egg protein shake."
The health-care professional may ask questions about the symptoms, when they started, and how long they have lasted. A review of systems may help give direction as to what type of infection is present. For example, a patient with numbness of their feet and weakness may be asked about whether they have opened any home canned food recently.
Travel history may be helpful to see if the patient had been camping near a stream or lake and the potential for drinking contaminated water, or if they have traveled out of the country recently and have eaten different foods than they normally do, such as raw eggs or wild game.
Physical examination begins with taking the vital signs of the patient (blood pressure, pulse rate, and temperature). Clinical signs of dehydration include dry, tenting skin, sunken eyes, dry mouth, and lack of sweat in the armpits and groin. In infants, in addition to the above, subtle signs of dehydration may include poor muscle tone, poor suckling, and sunken fontanelle.
Routine blood tests are not usually ordered unless there is concern about something more than the vomiting and diarrhea. In patients with significant dehydration, the health-care professional may want to check electrolyte levels in the blood as well as kidney function. If there is concern about hemolytic uremic syndrome, a complete blood count (hemogram, CBC) to check the red blood cells, white blood cells, and platelet count may be ordered. If there is concern about hepatitis, liver function tests may be ordered.
Stool samples may be useful especially if there is concern about infections caused by Salmonella, Shigella, and Campylobacter, the common non traveler's diarrhea. This is especially true when the patient presents with bloody diarrhea, thought to be due to infection. If there is concern about a parasite infection, stool samples can be examined also for the presence of parasites. Some parasites may be very difficult to see under the microscope, including Cyclospora, because it is so tiny.
Depending on the suspected cause of the food poisoning, there are some immunological tests (for example, detection of Shiga toxins) that the CDC recommends. Cyclospora DNA may be detected in the stool using molecular testing called polymerase chain reaction (PCR). Other methods may be used (for example, detection of prions in tissue samples).
Food poisoning can usually be treated at home, and most cases will resolve within three to five days.
If you have food poisoning, it’s crucial to remain properly hydrated. Sports drinks high in electrolytes can be helpful with this. Fruit juice and coconut water can restore carbohydrates and help with fatigue.
Avoid caffeine, which may irritate the digestive tract. Decaffeinated teas with soothing herbs like chamomile, peppermint, and dandelion may calm an upset stomach.
Over-the-counter medications like Imodium and Pepto-Bismol can help control diarrhea and suppress nausea. However, you should check with your doctor before using these medications, as the body uses vomiting and diarrhea to rid the system of the toxin. Also, using these medications could mask the severity of the illness and cause you to delay seeking expert treatment.
It’s also important for those with food poisoning to get plenty of rest.
In severe cases of food poisoning, individuals may require hydration with intravenous (IV) fluids at a hospital. In the very worst cases of food poisoning, a longer hospitalization may be required while the individual recovers.
Food safety tips
Prevention of food borne illness begins at home with proper food preparation technique.