Food poisoning occurs when you eat food contaminated with bacteria, viruses, parasites, or toxins. Symptoms include diarrhea, vomiting, and stomach cramps. Food poisoning generally starts 2 to 6 hours after eating contaminated food. Food poisoning is often caused by bacteria. However, it can also result from eating chemicals in poisonous plants (some mushrooms, for instance) and animals (puffer fish). Food poisoning is especially common during summer when food may not be kept cold enough to prevent bacteria from growing.
Signs and Symptoms
The typical signs of food poisoning are nausea, vomiting, abdominal cramping, diarrhea, head or muscle aches, and fever. Specific bacteria may cause these additional signs and symptoms:
Fish poisoning causes nausea, vomiting, diarrhea, abdominal pain, dizziness, and headache. Specific types of fish poisoning can cause other signs and symptoms, such as:
What Causes It?
Usually bacteria and algae cause food poisoning. However, poisonous plants and animals are other potential causes.
Common bacterial causes include:
Common types of fish poisoning include:
Mushroom poisoning occurs from eating poisonous wild mushrooms, especially Amanita phalloides.
Who's Most At Risk?
Infants and the elderly are at greater risk for food poisoning. Other risk factors include:
Listeriosis is common in pregnant women and people with immune problems. When a fetus is infected with listeria, it may be born prematurely or die.
What to Expect at Your Provider's Office
Your health care provider will examine you for signs and symptoms of food poisoning, such as stomach problems, neurologic problems, and dehydration.
Your health care provider may also ask about foods you have eaten recently, where you may have traveled, and if you have had contact with people showing similar symptoms.
Tests of your vomit, blood, and stool can sometimes identify the cause.
In the case of botulism, your health care provider may request serum and stool test (to confirm botulinum neurotoxin) and electromyography (a test to measure electric impulses in the muscles) to confirm the diagnosis.
Although brain imaging and lumbar puncture (spinal tap) results are normal in patients with botulism, they may be done to check for signs and symptoms related to central nervous system disorders.
These steps can help prevent food poisoning:
If others may have eaten a food that made you sick, let them know. If you think the food was contaminated when you bought it from a store or restaurant, tell the staff and your local health department.
Treatment for most cases of food poisoning involve replacing fluids and electrolytes (such as sodium, potassium, magnesium, and chloride). While experiencing vomiting and diarrhea, the person should avoid solid food but increase clear liquids. In more severe cases, a person may need help either breathing or stopping vomiting. Health care providers usually don't prescribe antibiotics because they may prolong diarrhea. If you have eaten certain toxins (such as from mushrooms or shellfish), your health care provider may take steps to clean out your stomach (a process called lavage, or pumping the stomach) and administer activated charcoal, which can help absorb the remaining toxin.
Depending on the symptoms, cause, and severity of food poisoning, a health care provider may prescribe drugs, including:
Complementary and Alternative Therapies
If you are suffering from severe food poisoning, seek conventional medical treatment. Complementary and alternative therapies are best used to strengthen the body and aid in the prevention of food poisoning.
The following general nutritional guidelines may be helpful in the case of food poisoning:
Various herbs have been used traditionally to treat different types of food poisoning. More research is needed. The following herbs should not be used in place of conventional medical care and are listed only for the purposes of discussion.
Animal studies of Chinese and Japanese combination herbal remedies used for Listeria suggest they may be effective for food poisoning. Active ingredients include Asian ginseng (Panax ginseng), Astragalus root (Astragalus membranaceus), Chinese cinnamon bark (Cinnamomum aromaticum), ginger root (Zingiber officinale), licorice (Glycyrrhiza glabra), peony root (Paeonia officinalis), or skullcap (Scutellaria lateriflora). No human studies have confirmed these effects. Do not take these herbs if you have high blood pressure, heart disease, or are taking blood-thinning medication (such as warfarin). Other drug interactions or dangerous side effects are possible, so make sure you discuss any herbal treatment with your provider.
Barberry (Berberis vulgaris) has been used traditionally to treat diarrhea from infectious causes such as E. coli and V. cholera. Berberine, the active ingredient in barberry, is also present in other plants (goldenseal, Oregon grape, and goldthread). Berberine can cause brain damage in newborns. Pregnant women should avoid berberine. Berberine may also lower blood sugar so patients with hypoglycemia or on diabetes medication should use caution. Other side effects are possible so speak to a physician before using berberine-containing herbs.
Studies examining the effectiveness of homeopathic remedies for food poisoning are lacking. Before prescribing a remedy, homeopaths take into account a person's constitutional type -- their physical, emotional, and intellectual makeup. Below are some more common remedies for food poisoning or diarrhea:
Most cases of food poisoning are mild and clear up on their own within 4 to 7 days. However, with mushroom (especially Amanita) poisoning, serious complications may occur and liver transplantation may become necessary. If treated early, the mortality is about 5% to 10%. With botulism, less than 10% die, and some people may need help breathing for months afterward. Many poisonings from pufferfish are fatal, however global statistics are lacking. Death is rare in other fish poisonings, but nerve-related symptoms can continue for months.
The following are some possible after effects of food poisoning:
For a severe case of food poisoning, you may need to stay in the hospital to receive fluids and electrolytes, so health care providers can monitor your breathing. Doctors may need to insert a tube down the throat (intubate) or connect you to a machine to help with breathing. Dialysis may be required. Cathartics (substances that help the body remove waste), enemas, and lavage may help eliminate toxins.
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Review Date: 4/9/2018
Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network. Also reviewed by the A.D.A.M. Editorial team.
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