Home Health A-Z Food Poisoning – Causes, Symptoms and Treatment

Food Poisoning – Causes, Symptoms and Treatment

Verified By Apollo General Physician February 13, 2021 39126 0
Food Poisoning
Food poisoning

What is Food Poisoning?

Food poisoning, also called foodborne illness, is illness caused by eating contaminated food. Infectious organisms — including bacteria, viruses and parasites — or their toxins are the most common causes of food poisoning. Infectious organisms or their toxins can contaminate food at any point of processing or production.

Food poisoning is not uncommon, although it is unpleasant. Every year, 48 million Americans (about one out of every seven) get food illness, according to the Centers for Disease Control and Prevention (CDC). 128,000 of the 48 million people are in hospitals.

About Food Poisoning

Food poisoning was first observed in the 1880s and came to be synonymous with stomach flu. The number of people contracting gastric illness increased, and today 1 out of every 10 people suffer from the condition at one time or another.

How food poisoning affects you will depend on how well your immune system fights the infection People often feel weak in the initial. If the condition becomes severe, loss of appetite is noticed in the patient.

In very rare cases, there is a need to see a doctor; otherwise, the illness resolves in a week or two. People of old age are at higher risk for suffering a case of food poisoning due to a weak immune system that cannot fight infectious organisms easily.

What are the symptoms of food poisoning?

Depending on the cause of the illness, the symptoms may differ. The following are some of the most common signs and symptoms of food poisoning:

Food poisoning can cause a variety of symptoms, including:

  • A bout of diarrhoea that lasts more than three days
  • A temperature of more than 102°F (38.9°C)
  • Having trouble seeing or speaking
  • Dry mouth, little to no pee, and trouble keeping fluids down are all indicators of severe dehydration.
  • Bloody urine  

When should you consult a doctor?

In most cases, it is not required to see a doctor for a case of food poisoning. Very rarely, a severe case of this condition can present, primarily in the elderly or individuals with a weak immune system.

When the following symptoms get aggravated, you should see a doctor:

  • Diarrhea for more than three days
  • Frequent vomiting
  • Bloody stool
  • Dizziness or blurry vision
  • An oral temperature higher than 100.4 F (38 C)
  • Extreme dehydration with dry mouth, sunken eyes, and reduced urination

If an infant has a fever of 101 degrees and is dehydrated, then it is recommended to see a doctor.

What are the causes of food poisoning?

Bacteria, parasites, and viruses are the three most common causes of food poisoning.

Almost the majority of the food humans eat has these germs. On the other hand, cooking usually destroys viruses in food before they reach our plates. Because raw foods do not go through the cooking process, they are a common source of food illness.  

Food will occasionally come into contact with microbes found in faeces or vomit. This is most likely to happen when a sick person prepares food without washing their hands beforehand. Contaminated meat, eggs, and dairy products are common. Water can also be contaminated with pathogenic organisms.


By far the most common cause of food poisoning is bacteria. Food poisoning can be caused by bacteria such as:

  • Shiga toxin-producing E. coli (STEC) is a kind of E. coli 
  • Listeria monocytogenes 
  • Salmonella
  • Campylobacter
  • Botulinum toxin Clostridium botulinum
  • Staphylococcus aureus is a kind of bacteria.
  • Shigella
  • Vulnerable Vibrio vulnificus


Food poisoning from parasites is less prevalent than from bacteria, yet parasites that transmit through food are exceedingly deadly. They are as follows:

  • Toxoplasma gondii is a parasitic infection caused by Toxoplasma Gondi
  • Giardia lamblia is a parasitic worm.
  • A variety of tapeworms, including:
  • Taenia saginata is a species of Taenia (beef tapeworm)
  • Taenia solium is a species of Taenia (pork tapeworm)
  • Diphyllobothrium latum is a species of Diphyllobothrium (fish tapeworm)
  • Cryptosporidium
  • A form of roundworm known as Ascaris lumbricoides.
  • Opisthorchiidae (liver fluke) and Paragonimus (flatworms) are examples of flukes (flatworms) (lung fluke)
  • Enterobiasis, or pinworms
  • Trichinella


A virus can also induce food poisoning, such as 

Common sources

Cause of food poisoningHow soon symptoms start (after exposure)Where it’s found
Ascaris lumbricoidesRarely causes noticeable symptomsProduce grown in contaminated soil
Astrovirus4–5 daysContaminated water
Campylobacter2–5 daysRaw or undercooked chicken, unpasteurized milk, contaminated water
Clostridium botulinum18–36 hoursPreserved vegetables that are low in acid (like green beans and mushrooms), canned tuna, fermented fish, ham, sausage, pruno (“prison wine”), items that have been improperly canned or bottled at home
Cryptosporidium2–10 days (7 days on average)Fresh fruits, fruit juice, fresh vegetables, unpasteurized apple cider, unpasteurized milk, contaminated water
Diphyllobothrium latum (fish tapeworm)Rarely causes noticeable symptomsRaw or undercooked fish
E. coli3–4 daysRaw or undercooked beef, raw lettuce and other vegetables, raw sprouts, unpasteurized milk, contaminated water
Enterobiasis (pinworms)Rarely causes noticeable symptomsMostly transmitted by touching a contaminated surface or through close contact with a person who has a case, but can also be caused by improper food handling
Giardia lamblia1–2 weeksProduce grown in contaminated soil, contaminated meat, contaminated water  Can also be caused by improper food handling
Hepatitis A virus15–50 daysFrozen berries, frozen vegetables, undercooked shellfish, contaminated water Can also be caused by improper food handling
Listeria monocytogenes1–4 weeksUnpasteurized dairy (like milk and soft cheeses), melon, raw sprouts, deli meat, smoked fish
Norovirus1–2 daysOysters and other shellfish, lettuce and other leafy greens, fresh fruit, contaminated water  Can also be caused by improper food handling
Opisthorchiidae (liver fluke)Rarely causes noticeable symptomsRaw or undercooked crab, crawfish, or fish
Paragonimus (lung fluke)2–15 daysRaw, undercooked, pickled, or salted crab or crawfish
Rotavirus1–2 daysShellfish, salads, contaminated ice
Salmonella6 hours–6 daysRaw or undercooked poultry, eggs, raw fruits and vegetables, contaminated water
Sapovirus1–3 daysOysters, clams, contaminated water
ShigellaUsually 1–2 days (but can take up to 7 days)Raw vegetables, cold salads like tuna salad and potato salad, sandwiches, contaminated water  Can also be caused by improper food handling
Staphylococcus aureus30 minutes–8 hoursPuddings, cream-filled baked goods, sliced meats, cold salads like tuna salad and potato salad, sandwiches  Can also be caused by improper food handling or leaving foods at improper temperatures
Taenia saginata (beef tapeworm)Rarely causes noticeable symptomsRaw or undercooked beef
Taenia solium (pork tapeworm)Rarely causes noticeable symptomsRaw or undercooked pork
Toxoplasma gondiiRarely causes noticeable symptomsUndercooked shellfish or meat (specifically pork, lamb, and venison), contaminated water.  Mostly transmitted through contact with infected cat faeces, but can also be caused by improper food handling or preparation
Trichinella1–2 days for abdominal symptoms and 2–8 weeks for other symptomsRaw or undercooked meat, specifically pork and wild game
Vibrio vulnificus2–48 hoursRaw or undercooked shellfish, especially oysters

How to Treat Food Poisoning at Home?

Food poisoning is typically treatable at home. Here are a few things you can do to aid with food poisoning:

  • Stay hydrated: It’s critical to stay hydrated if you’ve had food sickness. Electrolyte-rich sports beverages can be beneficial. Fruit juice and coconut water can aid fatigue and carbohydrate replenishment. Caffeine, which can irritate the digestive tract, should be avoided. Teas with soothing herbs like peppermint, dandelion, and chamomile and, which are decaffeinated, can help soothe an upset stomach. 
  • Take over-the-counter (OTC) medications : Loperamide and Pepto-Bismol are two over-the-counter (OTC) drugs that can help you control diarrhoea and nausea. But, you should see a doctor before taking these treatments because the body eliminates the poison through vomiting and diarrhoea. Additionally, taking these medications may conceal the severity of your disease, causing you to procrastinate getting professional help. Pyrantel pamoate (Reese’s Pinworm Medicine) is a popular pinworm treatment.
  • Take prescription medications : Although most food poisoning cases resolve independently, depending on the organism that caused their illness, some patients may benefit from prescription drugs. People who are older, immunocompromised, or pregnant may benefit from prescription drugs. Antibiotic medication during pregnancy helps to prevent infection from spreading to the unborn child.
  • Receive an antitoxin : A C. botulinum infection is considered a medical emergency. Seek medical attention as soon as possible. A doctor will administer an antitoxin if you have C. botulinum. BabyBIG, a unique antitoxin, will be given to the babies (botulism immune system globulin).
  • Home remedies : Without therapy, food illness usually improves within 48 hours. Try the following to keep yourself more comfortable and avoid dehydration as you recover:
  • Allow time for your stomach to settle.
  • Sucking on ice chips or drinking little sips of water are two options.
  • Probiotics
  • Reintroduce yourself to eating.
  • Rest till you feel better. 
  • Avoid specific foods and substances until you feel better.
  • If your case is severe : You may need intravenous (IV) fluid hydration at a hospital if you have severe food illness. In the most serious cases of food poisoning, you may have to stay in the hospital for a longer period of time to recover. Severe cases of C. botulinum, which are uncommon, may necessitate artificial breathing.

What to eat and drink if you have food poisoning

It’s advisable to avoid solid foods until the diarrhoea and vomiting have subsided. Instead, ease yourself back into your regular eating routine by eating or drinking bland, low-fat foods like:

  • Crackers with saltine
  • Toast
  • Gelatine
  • Bananas
  • Rice
  • Oatmeal
  • Potatoes with a dull flavour
  • Cooked vegetables 
  • Broth made with chicken
  • Ginger ale or root beer are examples of non-caffeinated sodas.
  • Fruit juices that have been diluted
  • Sports beverages

Foods to avoid

Even if you believe you’re feeling better, try to avoid the following harder-to-digest meals to avoid aggravating your stomach:

Examples of dairy products include milk and cheese

  • Foods high in fat
  • Foods that have been fried
  • Dishes with a lot of flavour
  • Foods with a lot of sugar
  • Spicy meals

Also stay away from:

How is food poisoning diagnosed?

Based on your symptoms, a doctor may be able to diagnose the sort of food poisoning you have. Blood tests, stool testing, and tests on the food you’ve eaten may be used to discover what’s causing the food poisoning in severe situations. A urine test may also be used by a doctor to determine if you are dehydrated as a result of food poisoning.

Risk factors for food poisoning

Food poisoning can strike anyone at any time. Food poisoning affects nearly everyone at some point in their lives, according to statistics.

There are some groups that are more vulnerable than others. These are some of them:

  • People with weakened immune systems – Anyone with a weakened immune system or an autoimmune condition may be more prone to infection and consequences as a result of food poisoning.
  • People who are expecting a child Pregnant women are more vulnerable since their bodies are adjusting to their metabolism and circulatory system changes.
  • Adults in their later yearsAdults aged 65 and up are also at a higher risk of developing food poisoning. This is due to the fact that their immune systems may not be able to respond rapidly enough to pathogenic germs.
  • Children in their early years Because their immune systems aren’t as developed as adults’, children below the age of five are also considered at-risk. Dehydration from vomiting and diarrhoea is more quickly absorbed by young children.

How to prevent food poisoning?

The easiest approach to avoid getting food poisoning is to handle your food carefully and avoid eating anything that could be dangerous.

Because of the way some foods are made and processed, they are more prone to induce food poisoning. Certain foods may contain infectious pathogens that are killed during cooking, such as:

  • Meat
  • Poultry
  • Eggs
  • Shellfish

Food poisoning can develop if certain foods are consumed raw, improperly cooked, or if hands and surfaces are not thoroughly cleansed after contact.

Food poisoning can also be caused by the following foods:

  • Raw or undercooked sushi and other raw or undercooked fish products
  • Hot dogs and deli meats that haven’t been heated or cooked
  • Flesh from a variety of animals can be found in ground beef.
  • Milk, cheese, and juice that hasn’t been pasteurized
  • Fruits and veggies that haven’t been washed

Take the following measures to avoid food poisoning:

  • Your hands should always be washed before cooking or eating.
  • Make sure your food is wrapped and kept appropriately.
  • Cook the meat and eggs well.
  • Before utilizing anything that has come into contact with raw items to cook other dishes, be sure it is clean.
  • Before serving, be sure to wash all fruits and vegetables.

What are the complications of food poisoning?

Complications with food poisoning are extremely rare, so there is nothing to worry about if you have normal symptoms.

Possible complications generally occur due to severe types of bacteria such as botulism. Such cases of food poisoning result from having undercooked food or food which isn’t stored properly.

The most common complications are:

It is important to keep in mind that these are very rare scenarios and mostly present in individuals who are already medically vulnerable.

Difference between stomach flu and food poisoning

Stomach fluFood poisoning
Stomach flu is caused by various viruses.Food poisoning can spread through bacteria, viruses, or parasites.
Symptoms of stomach flu take longer to develop than those of food poisoning.Food poisoning does not take longer to develop
Stomach flu is rare and can be contracted by coming in contact with a sick person or accidentally being exposed to the virus.Food poisoning mostly results from an individual ingesting contaminated food or water.


It is an uncomfortable health condition, but the good thing is it lasts only about two to three days. It takes only a few basic measures to avoid being exposed to organisms that cause food poisoning. If the symptoms get worse, see a doctor as soon as possible.

Frequently Asked Questions

Can you die from food poisoning?

Rarely, food poisoning can lead to death. In severe cases, kidney failure or brain damage can occur, which, without proper treatment, can lead to death.

How quickly does food poisoning kick in?

The signs and symptoms may appear immediately after ingesting the infected food, or they may appear days or even weeks in the future. Food poisoning symptoms may persist anywhere from some hours to many days.

Difference between food poisoning and food infection?

Food poisoningFood infection
Ingestion of live bacteria in meals causes it.Ingestion of a pre-formed poison in food causes it.
Disease may be caused by microorganisms as well as the poison they produce.Disease is caused by the poison produced by microorganisms, not by the microorganisms themselves.
E.g., includes: Salmonellosis, Shigellosis, gastroenteritis caused by vibrio spp., E. coli.E.g., includes: disease caused by Clostridium botulinum, Staphylococcus aureus, etc.

How to get relief from stomach pain due to food poisoning?

As your stomach settles, stop eating for the first few hours. Replace the minerals you lose during diarrhoea and vomiting with water, broth, or an electrolyte solution. Start with tiny portions of bland, non-fat items like toast, rice, and crackers when you’re ready. Get a lot of rest.

What are the different types of Food Poisoning?

There are at least 250 different types of food poisoning, but the most frequent are e. coli, listeria, salmonella, and norovirus, also known as ‘stomach flu.’ Botulism, campylobacter, vibrio, and shigella are some of the less frequent infections that can be transmitted by food or food handling.

Verified By Apollo General Physician

Our expert general medicine specialists verify the clinical accuracy of the content to deliver the most trusted source of information, making the management of health an empowering experience.

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