Food poisoning occurs when you eat food contaminated with bacteria or other toxins. Symptoms include diarrhea, vomiting, and stomach cramps, and generally start 4 - 36 hours after eating contaminated food. While food poisoning is often caused by bacteria, it can also result from eating poisonous plants (some mushrooms, for instance) and animals (pufferfish). Every year, more than 76 million people get sick from food poisoning, especially during summer when food may not be kept cold enough to prevent bacteria from growing.
The typical signs of food poisoning are nausea, vomiting, abdominal cramping, diarrhea, head or muscle aches, and fever. Specific bacteria may cause these 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:
Usually bacteria and algae cause food poisoning, but poisonous plants and animals may also be the cause.
Common bacterial toxins include:
Common types of fish poisoning include:
Mushroom poisoning occurs from eating wild poisonous mushrooms, especially Amanita phalloides.
Infants and the elderly are at greater risk for food poisoning. Other risk factors include:
Listeriosis is most common in pregnant women, fetuses, and people with immune problems. When a fetus is infected with listeria, it may be born prematurely or die.
Your health care provider will examine you for signs and symptoms of food poisoning, such as stomach 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 identify the cause. In the case of botulism, your health care provider may request electromyography (a test to measure electric impulses in the muscles) to confirm the diagnosis. A lumbar puncture (spinal tap) 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. In most cases, health care providers do not 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:
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. For example, animal studies have shown that certain vitamins and nutrients may protect against some food toxins while others may actually worsen the effects of toxins. Milk thistle is an herb commonly used in Europe as a primary treatment for mushroom poisoning. Homeopathy may help treat diarrhea in children (which is sometimes caused by food poisoning) in developing countries.
The following general nutritional guidelines may be helpful in the case of food poisoning:
For specific types of food poisoning:
Supplements to avoid:
Various herbs have been used traditionally to treat different types of food poisoning, though in most cases more research is needed.
Milk thistle (Silybum marianum) is often used for liver disorders and is widely used in Europe to treat Amanita mushroom poisoning. Studies show that patients with Amanita poisoning can be effectively treated with pharmaceutical silibinin (the primary active component of milk thistle) up to 48 hours after eating the deadly mushrooms.
Animal studies of Chinese and Japanese combination herbal remedies used for Listeria suggest they may be effective for food poisoning. Active ingredients include:
Seek the advice of a trained and licensed herbalist or practitioner of Traditional Chinese Medicine who will guide your individual treatment. Do not self treat with these herbs. Some of these herbs should not be taken if you have heart disease, or high blood pressure, or take blood thinning medication. In addition, some of these herbs interact with other herbs, supplements, and prescription medications, so it is important to make sure all your health care providers know what you are taking.
Laboratory (test tube) studies suggest that the following herbs have antibacterial or antimicrobial properties, although there is no evidence they are effective for treating food poisoning in humans. Do not use these herbs without speaking to a physician or knowledgeable herbal practitioner. Some side effects can be dangerous:
Barberry (Berberis vulgaris) has also been used traditionally to treat diarrhea from infectious causes such as E. coli and V. cholera. Berberine, the active ingredient in barberry, can cause brain damage in newborns. Speak to a physician before using berberine containing herbs with children of any age.
No studies have examined the effectiveness of homeopathic remedies for food poisoning. Before prescribing a remedy, homeopaths take into account a person's constitutional type -- your physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors when determining the most appropriate remedy for a particular individual. 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 - 7 days. However, with mushroom poisoning, up to half of people may die. With botulism, less than 10% die, and some people may need help breathing for months afterwards. More than half of poisonings from pufferfish are fatal. 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.
Abubakar I, Irvine L, Aldus CF, et al. A systematic review of the clinical, public health and cost-effectiveness of rapid diagnostic tests for the detection and identification of bacterial intestinal pathogens in feces and food. Health Technol Assess. 2007;11(36):1-216.
Beers MH, Porter RS, et al. The Merck Manual of Diagnosis and Therapy. 18th ed. Whitehouse Station, NJ: Merck Research Laboratories; 2006:1642-1644.
Blumenthal M, Goldberg A, Brinckmann J, eds. Herbal Medicine: Expanded Commission E Monographs. Boston, Mass: Integrative Medicine Communications; 2000:257.
Bovee-Oudenhoven IM, Wissink ML, Wouters JT, Van der Meer R. Dietary calcium phosphate stimulates intestinal lactobacilli and decreases the severity of a salmonella infection in rats. J Nutr. 1999;129:607-612.
Chan YC, Wiedmann M. Physiology and genetics of Listeria monocytogenes survival and growth at cold temperatures. Crit Rev Food Sci Nutr. 2009;49(3):237-53.
Duncan SH, Flint HJ, Stewart CS. Inhibitory activity of gut bacteria against Escherichiacoli 0157 mediated by dietary plant metabolites. FEMS Microbiol Lett. 1998;164:238-288.
Facey PC, Pascoe KO, Porter RB, Jones AD. Investigation of plants used in Jamaican folk medicine for anti-bacterial activity. J Pharm Pharmacol. 1999;51:1455-1460.
Ferri. Ferri's Clinical Advisor 2011, 1st ed. Philadelphia, PA: Mosby; 2010.
Fritsche KL, Shahbazian LM, Feng C, Berg JN. Dietary fish oil reduces survival and impairs bacterial clearance in C3H/Hen mice challenged with Listeria monocytogenes. Clin Sci. 1997;92:95-101.
Gabriel EP, Lindquist BL, Abud RL, Merrick JM, Lebenthal E. Effect of vitamin A deficiency on the adherence of fimbriated and nonfimbriated Salmonella typhimurium to isolated small intestinal enterocytes. J Ped Gastroenterol Nutr. 1990;10:530-535.
Hatchigian EA, Santon JE, Broitman SA, Vitale JJ. Vitamin A supplementation improves macrophage function and bacterial clearance during experimental Salmonella infection. PSEBM. 1989;191:47-54.
Hruby K, Csomos G, Fuhrmann M, Thaler H. Chemotherapy of Amanita phalloides poisoning with intravenous silibinin. Hum Exp Toxicol. 1983;2(2):183-195.
Irons R, Anderson MJ, Zhang M, Fritsche KL. Dietary fish oil impairs primary host resistance against Listeria monocytogenes more than the immunological memory response. J. Nutr. 2003 Apr;133:1163-1169.
Jacobs J, Jiménez-Pérez M, Malthouse S, Chapman E, Crothers D, Masuk M, Jonas WB. Homeopathic treatment of acute childhood diarrhea: results from a clinical trial in Nepal. J Altern Complement Med. 2000;6(2):131-139.
Lee MH, Kwon HA, Kwon DY et al. Antibacterial activity of medicinal herb extracts against Salmonella. Int J Food Microbiol. 2006;111(3):270-5.
Mandell: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases 7th ed. Philadelphia, PA: Elsevier Inc.; 2009.
Pigott D. Foodborne Illness. Emergency Medicine Clinics of North America. Birmingham, AL: WB Saunders; 2008:26(2).
Rabbani GH, Butler T, Knight J, Sanyal SC, Alam K. Randomized controlled trial of berberine sulfate therapy for diarrhea due to enterotoxigenic Escherichia coli and Vibrio cholerae. J Infect Dis. 1987 May;155(5):979-984.
Sabeel AI, Kurkus J, Lindholm T. Intensive hemodialysis and hemoperfusion treatment of Amanita mushroom poisoning. Mycopathologia. 1995;131(2):107-114.
Verma RJ, Shalini M. Ochratoxin A-induced cytotoxicity to human red blood cells and its prevention by certain vitamins. Med Sci Res. 1997;25(12):833-834.
Yonekura K, Kawakita T, Mitsuyama M, Miura O, Yumioka E, Suzuki A, Nomoto K. Induction of colony-stimulating factor(s) after administration of a traditional Chinese medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to). Immunopharmacol Immunotoxicol. 1990;12(4):647-667.
Yonekura K, Kawakita T, Saito Y, Suzuki A, Nomoto K. Augmentation of host resistance to Listeria monocytogenes infection by a traditional Chinese medicine, ren-shen-yang-rong-tang (Japanese name: ninjin-youei-to). Immunopharmacol Immunotoxicol. 1992;14(1-2):165-190.
© 2011 University of Maryland Medical Center (UMMC). All rights reserved.
UMMC is a member of the University of Maryland Medical System,
22 S. Greene Street, Baltimore, MD 21201. TDD: 1-800-735-2258 or 1.866.408.6885