Reheating pasta can cause food poisoning

Food poisoning: causes, symptoms, treatment

SOS - what to do if you have food poisoning?

If very severe symptoms such as severe nausea, vomiting or even bloody diarrhea occur, a doctor should be consulted immediately. This is especially true when young children, the elderly or pregnant women have food poisoning.

If it is not clear which food caused the symptoms, the doctor should be given a few samples of the most recently consumed food for laboratory analysis. This is especially true after a mushroom meal. Then it may be necessary to administer a specific antidote.

Basically, it must be ensured that patients drink enough and balance their electrolyte balance. It is best to give the sick tea with sugar or water and an electrolyte solution from the pharmacy.

What is Food Poisoning?

Food poisoning is caused by toxins called toxins. They are either formed by bacteria in the food and thus get into the gastrointestinal tract. Or they arise only after the pathogen has entered the body with food. In most cases, the bacterium Staphylococcus aureus is responsible for food poisoning. Bacteria of the Bacillus cereus group or Clostridium species are less common.

Unlike food poisoning, food infection is contagious. The main triggers of gastrointestinal infections include Campylobacter bacteria, Salmonella and Listeria. EHEC bacteria, Yersinia viruses, hepatitis viruses, noroviruses and rotaviruses can also cause disease. The pathogens enter the gastrointestinal tract through food and multiply there. They can cling to the same food as food poisoning agents.

In Germany there is an obligation to report any food poisoning caused by bacteria. The food suspected of having the disease is checked in the laboratory. If it is confirmed that it is contaminated, the product will be withdrawn from the market immediately. A corresponding food warning is published for this purpose. Suspected food can be submitted for analysis by private individuals, grocery chains and competent authorities.

Food poisoning symptoms

Typical symptoms of food poisoning and also of a food infection are nausea, vomiting, diarrhea and abdominal cramps. However, depending on the specific cause of the poisoning, the symptoms may vary. If food poisoning occurs after eating spoiled or poisonous food, the symptoms can appear after a few minutes, or even after hours. If there is an infection with the Campylobacter bacterium, it is possible that the symptoms will only show up after a few days.

In most cases, the symptoms of food poisoning are mild and the condition heals on its own within a few days. However, it can also lead to severe poisoning, which causes very severe discomfort. Those affected then suffer from severe vomiting, bloody diarrhea or more than ten attacks of diarrhea a day. In this case, sick people should definitely see a doctor.

Cause of food poisoning

If pathogens trigger food poisoning or food infection, local epidemics often occur, for example in communal facilities, canteens or on cruise ships. Food poisoning from spoiled food is more common, especially during the summer months, because bacteria multiply faster in warm temperatures. In tropical and subtropical regions, too, the warm climate means that the conditions for the spread of pathogens are particularly favorable. Bad hygienic conditions in the cultivation of food, in its preparation and sale, increase the risk of food poisoning.

Viruses are also a common cause of food infections. They cannot multiply in food and do not spoil them. From the outside, the contamination with viruses is not perceptible either through smell or taste. A viral infection that causes gastrointestinal discomfort is often due to the consumption of food that has been contaminated with feces or contaminated water. The virus can also be transmitted through infection by infected people or through the consumption of the meat of infected animals. Viral gastrointestinal diseases can also occur epidemically in community facilities such as kindergartens, old people's homes or hospitals.

Basically, food poisoning can be traced back to different causes. These are for example:

  • Pathogen (food infection)
  • Poisonous mushrooms
  • Fish, mussels, crustaceans that are spoiled or contaminated with bacteria
  • Plant poisons
  • Food pollutants

When pathogens cause food poisoning or infection:

Food poisoning or food infection can be caused by a variety of pathogens. The triggers of the foodborne illness include salmonellosis, listeriosis and botulism. Depending on the particular pathogen, different symptoms appear.


Salmonella bacteria are responsible for salmonella poisoning. This often happens when raw or insufficiently heated animal foods are eaten. Eating raw eggs, for example, poses a high risk. Typical symptoms of salmonellosis include nausea, vomiting and abdominal cramps, especially chills and fever. It can also happen that the bacterial infection causes no symptoms at all in those affected.


Listeriosis is caused by bacteria of the Listeria genus. Listeria can be found in animal foods such as soft cheese (Roquefort or Brie), in raw milk and also in raw meat. In addition, the bacteria can multiply in vacuum packaging. Storing these foods in the refrigerator will not inhibit bacterial growth. An infection with Listeria usually does not cause any symptoms in otherwise healthy people. If symptoms do occur, these are often joint pain, muscle pain, vomiting, fever and diarrhea. If the listeria spread in the body, further symptoms can occur. It is dangerous when the listeria penetrate the brain and cause meningitis. Patients then suffer from a high fever, stiff neck and headache. It is also possible that the bacteria penetrate the bloodstream and lead to blood poisoning (sepsis). Furthermore, inflammation of the inner wall of the heart (endocarditis) or peritonitis (peritonitis) can be the result of listeriosis.

Listeriosis can lead to serious complications, especially in infants, the elderly and people with weakened immune systems. If a pregnant woman falls ill with the bacterial infection, this can lead to a miscarriage or stillbirth.


Infection with bacteria of the type Clostridium botulinum (Clostridia) is rare, but can be life-threatening. Most of those affected have eaten products from inflated cans or self-pickled fruit and vegetables. These can be possible triggers of the disease. Clostridia attack the nervous system and can lead to the first symptoms of paralysis of the eye muscles within 20 to 36 hours after consuming contaminated food. This is followed by a weakening of the skeletal muscles, speech disorders, slow heartbeat, decreased blood pressure, constipation and urinary retention. In addition, botulism sufferers suffer from dry mouth, swallowing and vision disorders, dry pupils, drooping eyelids and slow reflexes.

The poisoning takes on life-threatening proportions when nerves relevant for breathing are affected. If the patient is then not mechanically ventilated, death can result from respiratory failure. Treatment in hospital is therefore generally necessary.

Other bacterial causes:

Escherichia coli is a bacterium that is mainly found in raw beef and raw milk. E. coli can also be transmitted from person to person. The E. coli infection first leads to watery diarrhea, which can later be bloody.

Staphylococci usually end up in food due to poor hygiene in the kitchen. Food poisoning with the bacteria leads to low temperature and poor circulation. Staphylococci cannot be rendered harmless by heating food.

Yersinia is mostly transmitted through contact with infected animals or through the consumption of contaminated food. Food infection with Yersinia causes headache, fever, and chills.

Campylobacter bacteria can be found in poultry meat that has not been sufficiently heated and in products made with raw eggs. Sick people get a high fever, watery diarrhea, headaches and are very tired. The pathogens can be killed by thoroughly heating the food (boiling or frying).

Shigella are often found in warm regions and where hygienic conditions are inadequate. Food contaminated by Shigella has mostly come into contact with faeces or sewage. Drinking water can also be contaminated. Poisoning with these pathogens causes cramp-like abdominal pain, painful bowel movements and diarrhea.

If fish, mussels or crabs cause food poisoning:

If fish or mussel poisoning occurs, disease-causing bacteria could multiply in the animals. This can happen if the food has either been stored incorrectly or for too long. Another reason for food poisoning after consuming fish can be the toxin ciguatoxin. It is produced by unicellular organisms that live in the water and that can find their way into fish through the food chain. Symptoms of poisoning with the toxin include nausea, vomiting, and diarrhea. - Even naturally poisonous fish can lead to food poisoning. Puffer fish contain the neurotoxin tetrodotoxin. Consumption of this fish can lead to death if improperly prepared.

When mushrooms cause food poisoning:

Mushroom poisoning causes symptoms such as stomach pain, nausea, and vomiting. In addition, those affected often suffer from sweating, chills, dizziness, impaired consciousness, shortness of breath, palpitations and disorders of balance. The severity of the symptoms depends on the type of mushroom consumed and also on the amount of mushroom toxin. Consuming some types of mushrooms can be fatal. Poisonous mushrooms are, among others, fly agaric, death cap mushroom and spring lobster. - The doctor should know which mushrooms were eaten. It is usually also helpful for treatment if leftovers from the meal or vomit have been saved. Samples can be analyzed for the triggering toxin in the laboratory.

When plants cause food poisoning:

Numerous plants produce toxins to protect against predators. These plants can then often be poisonous to humans in even small quantities. Children often suffer food poisoning from such poisonous plants, as they often put parts of plants in their mouths out of curiosity without adults noticing. The poisonous plants found in this country include: ivy, yew, laburnum, angel's trumpet, autumn crocus, lily of the valley, monkshood, foxglove and henbane. Consumption of some of these plants can cause respiratory paralysis or heart failure, and thus death. If there is any suspicion that a child or another person has eaten poisonous plants, the emergency doctor should be called immediately.

When pollutants cause food poisoning:

It happens that food is contaminated with toxic metals or metal compounds (lead, cadmium, mercury, zinc). This can cause symptoms of intoxication. This happens especially when a larger amount of the pollutants is ingested or when small doses of the poison are taken in regularly. Organic lead compounds can damage the central nervous system and lead to hallucinations, excitement or cramps. The long-term effects of such poisoning include Parkinson's-like symptoms and paralysis.

Food Poisoning Diagnosis

Often times, food poisoning will heal on its own. However, if children, pregnant women or the elderly are affected, a doctor should be consulted immediately. The symptoms should always be clarified by a doctor if the symptoms persist for more than three days and if there is a fever or bloody diarrhea.

Sick people should tell the doctor exactly how their symptoms are expressed, but also what food they last eaten. If mushroom dishes or foods that may have tasted or smelled strange have been consumed, this can already give the doctor an indication of food poisoning. In the event of severe disease, the doctor will have samples of stool and blood analyzed in the laboratory to identify the pathogen. For example, if botulism is suspected, the patient's stool or vomit will be examined. Since the laboratory analysis for botulinum toxin takes about 24 hours, but the disease is dangerous, the doctor usually starts the appropriate therapy if botulism is suspected. If certain foods are suspected to have caused the disease at the beginning of the diagnosis, a sample of the suspicious foods can also be examined in order to be able to detect possible pathogens or toxins. For the treatment of the patient, it can be very important to know the pathogen or the exact toxin.

Obligation to report food poisoning

For every food poisoning caused by bacteria there is an obligation to report in Germany. In order to avoid further illnesses, contaminated food can be withdrawn from the market (publication of a food warning).

Food Poisoning Treatment

The treatment of food poisoning depends on its cause and the patient's complaints. If the course is severe, hospital treatment is usually required. Since the symptoms of food poisoning are usually vomiting and diarrhea, the sick lose a lot of fluids and electrolytes. To compensate for this, it is important to drink enough fluids and to supply electrolytes. Drinks like tea with sugar or still water are best. Electrolyte solutions are available in the pharmacy, but you can also make your own. For this salt-sugar solution, add five tablespoons of sugar, one and a half level tablespoons of table salt and a glass of orange juice to one liter of water. If you fall ill while traveling and in unsafe hygienic conditions, you should make sure that the water has either been boiled or comes from a well-closed bottle. In this case, the orange juice should also come from a bottle and not be freshly squeezed. - Drink the salt and sugar solution slowly and in sips.

Despite illness, patients should start eating again as soon as possible. Easily digestible foods such as gruel, rusks, bananas, rice, white bread and broth are particularly suitable. On the other hand, fruit juices, raw vegetables, dairy products, fatty foods, soft drinks, coffee and alcohol are not suitable. These foods are difficult to digest or irritate the mucous membrane. - Since the gastrointestinal tract is still affected even after the illness has been overcome, it is better to rely on light foods for some time.

Drug therapy for food poisoning:

Diarrhea and vomiting are actually helpful, because pathogens and toxins leave the body in this way. Only if the symptoms are very severe should the symptoms be suppressed with the help of medication. The doctor then gives anti-emetics such as metoclopramide against nausea and vomiting, and anti-diarrheal drugs such as loperamide against diarrhea. Activated charcoal (medicinal charcoal) is used for some food poisoning because it binds bacterial pathogens and toxins in the digestive tract. Then everything is excreted in the stool.

In the case of bacterial food poisoning, for example listeriosis, and sometimes salmonellosis, the doctor will prescribe antibiotics. An antitoxin (antidote) is given to patients suffering from botulism. The agent must be administered as quickly as possible. Those affected are usually treated in the intensive care unit of a hospital, because artificial ventilation can be initiated immediately if necessary.

Infection-related diarrhea can sometimes be shortened by taking probiotics such as lactic acid bacteria. The microorganisms have a positive effect on the intestinal flora and can increase the number of so-called good germs in the intestine. They are found in various foods, including natural yoghurt, buttermilk, kefir and sauerkraut. Some probiotics also produce antibiotic defense substances against pathogenic germs and increase the activity of special immune cells.The exact mechanism of action of the individual bacterial strains is currently still the subject of research.

In the case of mushroom poisoning, the affected person is often pumped out of the stomach. Antidotes are also available for certain mushroom toxins. It is important for the doctor to know which mushrooms have been consumed. The pathogenic toxin is then searched for in the laboratory. Vomit can also be analyzed.

Homeopathy for food poisoning

Often it is a matter of infections or reactions to poorly tolerated food or drink when the body reacts with nausea, vomiting and diarrhea. The causes can be varied, but often food poisoning is behind it. If the symptoms are very severe or if they last for several days, a doctor should be consulted. Food poisoning can be very severe depending on its cause. Patients lose a lot of fluids and electrolytes through vomiting and diarrhea. It is therefore important to drink enough and also to balance the electrolyte balance. The following homeopathic medicines can be taken to alleviate the symptoms (selection):

  • Arsenicum album: For acute gastrointestinal infections with vomiting and diarrhea.
  • Okoubaka: For nausea, vomiting and diarrhea after eating spoiled food.
  • Carbo vegetabilis: When it comes to collapse after eating spoiled food.

Acupuncture for food poisoning

Acupuncture can be helpful when the immune system is weakened and patients are not as productive as before long after a previous illness. Food poisoning, especially if it is severe, can permanently weaken the patient. Thanks to therapy with acupuncture needles, the organism is supported in recovering more quickly. The gentle needling can also help the peristalsis of the stomach and intestines to normalize again.

Food Poisoning - Prevention

Thorough food hygiene is an important part of preventing food poisoning. The following tips should be observed:

  • Always wash fruit and vegetables thoroughly. This applies both before consuming the raw food and before preparing it for cooking.
  • Food that smells or tastes noticeable is better to throw away.
  • Clean all kitchen utensils before they are used and also after cooking. This is especially true when processing fish and meat.
  • Hands should always be clean before coming into contact with food. Hands should also be washed after preparing a meal.
  • Dishcloths and other cleaning aids for the kitchen should always be cleaned well and replaced regularly.
  • Remove jewelry before working with food. Food scraps could get stuck.
  • Wear clean clothes when cooking.
  • Always fry or cook fish and meat well. Wash the products well before preparing them.
  • Better to avoid raw milk products, raw fish and raw meat.
  • Note the expiration date of food.
  • Store food at the recommended temperatures. Many products stay fresh longer in well-sealable containers.
  • Be sure to thoroughly dispose of food if it is found to be infested with insects. This also applies in the event that pets or rodents such as rats or mice were on the food.
  • Pets should not be in the kitchen. Avoid insects and rodents in the cooking area.
  • Always dispose of packaging and defrosted water from meat products immediately.
  • When buying frozen products, the cold chain should only be interrupted briefly as possible. It is best to use a cooler bag, especially in summer.
  • Thaw frozen food in the refrigerator overnight. Not at room temperature. This is particularly important with fish, as the bacteria can multiply strongly in the thawing water. Rinse fish with water before preparing.
  • Always use fresh eggs when preparing food that contains raw eggs.
  • If a package is bloated or the lid of a can bulges, this could indicate contamination with Clostridium botulinum. The products must be disposed of immediately.

Avoid food poisoning while on vacation

When traveling to countries with poor hygienic conditions, you should make sure that you only drink water from bottles that are originally closed and never replace it with tap water. If there are ice cubes in drinks made from tap water, do not drink them. In case of doubt, you should only use boiled water or drinking water from bottles (originally sealed) to brush your teeth. Do not consume food that is raw or has not been sufficiently heated. These include fruit, vegetables, salads, juices and seafood. - It is best to always follow this rule: “Peel it, cook it or forget it.” (Peel it, cook it or forget it.).

Food Poisoning - ICD Code

In medicine, each illness is assigned its own ICD code. The abbreviation ICD stands for International Statistical Classification of Diseases and Related Health Problems. The classification system is recognized worldwide and is one of the most important for medical diagnoses. For example, food poisoning by staphylococci is recorded under the ICD code “A05.0”. Entering this code often helps with research on the Internet.

Food poisoning - what does the health insurance company pay for and what do you have to pay for yourself?

Members of a statutory health insurance basically have the right to inpatient and outpatient care, to drugs and other services. As a rule, however, certain personal contributions (additional payments) are stipulated by law. These additional payments amount to 10 percent of the costs, but a maximum of 10 euros per additional payment. If the service costs less than 5 euros, the insured person must pay the actual price.

These limits also apply to pharmaceuticals. If the person concerned receives a particularly inexpensive preparation, there is no additional payment. The health insurances can determine fixed amounts that they reimburse if several preparations with the same active ingredient are available. Medicines, the price of which is 30 percent below this fixed amount, are reimbursed by the health insurance companies without additional payment.

In addition, there is a regulation that the statutory health insurance no longer has to reimburse the individual price of the respective drug for certain preparations, but only the fixed amount that has been set for a group of comparable preparations. If the prescribed medication is more expensive, the patient has to pay the additional price himself plus the statutory additional payment for the reimbursed portion of the costs.

Co-payments are also incurred in the event of a hospital stay. They amount to 10 euros per calendar day, whereby the additional payment only has to be made for a maximum of 28 days per year. Several hospital stays can be combined in one year, so that the maximum additional payment for inpatient treatment is 280 euros per calendar year.

In the case of home nursing, a one-time fee of ten euros is due for the prescription. In addition, a personal contribution of 10 percent per day is to be borne. The co-payment is limited to 28 calendar days per calendar year and is only charged for adults over 18 years of age. The upper limit of EUR 280 per calendar year also applies to home care. Co-payments for hospital stays count towards the cap on co-payment for home nursing.

If the costs for household help are covered by the health insurance, the insured must make an additional payment of 10 percent of the costs incurred. The limits are at least 5 and a maximum of 10 euros per calendar day. This co-payment obligation applies to the entire period in which domestic help is used.

In the case of aids, the insured must make an additional payment of 10 percent of the selling price, with an upper and lower limit of 10 and 5 euros per prescription.

The amount of co-payments for rehabilitation measures depends on the measure and the respective cost bearer.

The costs for pain therapy in a pain clinic are usually covered by any statutory health insurance company, as it is a contracted medical service. However, additional costs (such as additional payments for prescriptions) may arise privately.

The costs of a classic body acupuncture are covered by all statutory health insurances for chronic pain in the lumbar spine or knee osteoarthritis. It is assumed that the pain has existed for at least six months. In such cases, legally insured persons are entitled to up to ten acupuncture sessions per case of illness within a maximum of six weeks. A new treatment can take place no earlier than twelve months after completion of the last acupuncture treatment. The health insurance will only reimburse the costs if the treatment is carried out by a qualified doctor. Acupuncture from a naturopath is not accepted. The costs are then to be paid privately.

Food poisoning - what does the DFV take care of?

The outpatient supplementary health insurance DFV-AmbulantSchutz reimburses you for additional payments provided for by law for medicines, bandages, remedies and aids and travel costs as part of outpatient treatment. The DFV-AmbulantSchutz also offers you extended pension benefits and is also there to support you financially if a serious illness is diagnosed.

In the event of illness, with the additional hospital insurance DFV-KlinikSchutz Exklusiv, you do not wait longer than 5 days for an appointment with a specialist doctor.

You also benefit from head physician treatment, a single room, free choice of hospital and daily hospital allowance for an inpatient clinic stay. DFV-KlinikSchutz makes you a private patient in the hospital including international health insurance.

Food poisoning FAQ

How Long Have You Been Food Poisoned?

The causes of food poisoning can be many. How long a patient is ill depends on the specific trigger and often also on the amount of poisons or germs ingested. In this way, mild food poisoning can heal within a few days. If the course is severe, for example due to botulism, a patient usually has to be treated in the hospital's intensive care unit. The recovery time then depends on the severity of the illness.

What are the symptoms of food poisoning?

Typical symptoms of food poisoning are nausea, vomiting, diarrhea, and abdominal cramps. Depending on the cause of the disease, other complaints can also occur. These include fever, chills, dizziness and impaired consciousness. Serious poisoning usually also leads to more severe symptoms. Therefore, you should definitely consult a doctor if you experience severe vomiting, bloody diarrhea or more than ten diarrhea per day.

What Helps With Food Poisoning?

Treatment for the condition will depend on what triggered the food poisoning. For example, mushroom poisoning may require pumping out the stomach or the administration of an antitoxin. In the case of a bacterial infection, the doctor often prescribes antibiotics. If food poisoning is less pronounced, the disease often heals on its own within a few days. Those affected should always make sure that they take in enough fluids and salts and thus balance their electrolyte balance. Because vomiting and diarrhea cause the body to lose a lot of water and minerals.

What can you eat after food poisoning?

As soon as a patient can, he should start eating again. In the beginning, however, only easily digestible foods such as rusks, white bread, rice, bananas, gruel or broth. Even after the symptoms have subsided, you should stick to light foods for several days. Because the gastrointestinal tract needs some time to completely regenerate.

Where can I report food poisoning?

If there is a suspicion of food poisoning, those affected can contact the health department and the mayor or district offices. In Germany there is an obligation to report any food poisoning caused by bacteria. In such a case, the attending physician will pass on the information accordingly.


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All statements without guarantee.