Symptoms of food poisoning
Most symptoms of food poisoning appear within a 2-6 hour period after consumption. If the illness is less severe, food poisoning may take days to become apparent. This will differ by type of contaminating organism. Symptoms, however, may persist for 24 hours or even a few days. Some pathogens are especially dangerous, as they can lead to other illnesses such as meningitis or miscarriage. Most food-borne infections share one or more of the following symptoms:

• abdominal pain
• fatigue, fever
• loss of appetite
• nausea
• stomach cramping
• vomiting
• watery diarrhea

Symptoms of food poisoning by type of bacteria or virus
The following lists more detail based on the organism, and what to look for. This can be useful in identifying the organism responsible:

Botulism – Onset from 4-72 hours. Signs of infection include droopy eyelids, double vision, difficulty speaking, swallowing, and breathing. Seek medical help immediately, as botulism can be fatal.

Campylobacteriosis – Onset from 2-10 days. Signs of infection include severe diarrhea (blood may be present), cramping, fever, persisting headache (1-10 days).

E. Coli – Onset usually between 3-4 days. Signs of an e-coli infection include severe abdominal cramping, diarrhea (blood may be present), nausea, vomiting, lasting fever (up to 10 days). Hospitalization may be necessary.

Hepatitis – Onset takes from 14-50 days. Signs and symptoms of a hepatitis infection fatigue, fever, nausea, vomiting, abdominal cramping, loss of appetite, yellowish pallor (jaundice), dark urine. May enlarge or damage the liver. Can be fatal.

Listeria – Onset of symptoms usually within 2-30 days. Signs of infection in adults: fever, chills, and intestinal flu-like symptoms. Signs of infection in infants: vomiting, breathing trouble, and refusing fluids. Listeria can be fatal in some cases.

Perfringens – Onset of this type of poisoning is fast and symptoms exhibit within 8-24 hours. Symptoms can include nausea, vomiting, gas pains, diarrhea.

Salmonella – Onset is within 6-48 hours. Signs and symptoms of salmonella poisoning include nausea, abdominal cramping, vomiting, headache, fever, diarrhea. Vomiting may last 2-7 days. Can be fatal in risk groups.

Shigella – Onset of symptoms is over 1-7 day(s) period. Signs of infection include abdominal pain, diarrhea, fever, possible vomiting. Blood, pus or mucus may appear in stool for 5-6 days.

Staph – Onset of staph infection is relatively fast and occurs within 1-8 hours. Symptoms of staph infection are nausea, vomiting, abdominal cramping, diarrhea. Cramping may last for 2 days.

Viruses – Onset is usually very quick and takes place within 24-48 hours of consumption. Signs of infection include diarrhea, nausea, abdominal cramping, vomiting, fever, chills, aches.

Complications
Dehydration is one common complication shared over all categories of food poisoning. Dehydration is due to salt, mineral, and fluid loss during vomiting and diarrhea but is normally not a danger to most adults. However, some groups have more difficulty replacing fluids and may be threatened by severe dehydration. These include infants, the aged, and those with suppressed immune systems. Some cases will need hospitalization, for monitoring and intravenous fluid replacement. Two specific types of poisoning need to be mentioned here due to the more serious complications they can bring:

E. Coli – Certain strains of E. coli can cause hemolytic uremic syndrome (HUS), a complication that can lead to kidney failure, and death. HUS can cause damage to the lining of the kidney’s smaller blood vessels.

Listeria – This type of bacterial food poisoning endangers the unborn. A woman suffering from a listeria infection may miscarry early in the pregnancy. In more mature fetuses, listeria can cause premature birth, fatal infections, even stillbirth. Those infants surviving infection may still suffer effects such as regressed development and neurological damage. Even when mothers have a mild infection, the resulting complications are dangerous to the baby.

When to seek help
The most common types of food poisoning are usually very minor, and the average person with normal health can recover within a 12-48 hour period. However, one must not ignore more severe and long-lasting symptoms, as complications can develop from certain types of food-borne illness. In the case of suspect seafood or mushrooms, immediate attention should be sought. Some toxins from these are deadly, and may require that the stomach be emptied to remove as much poison as possible. In addition, any of the following symptoms of food poisoning require prompt swift medical attention. Warning signs include:

• blood in stool
• dehydration symptoms such as excessive thirst, weakness, dizzy spells, lightheaded sensation, little/no urination, dry mouth
• diarrhea
• extreme abdominal pain
• frequent vomiting for 2 days or more
• inability to keep liquids down for 24 hours
• severe abdominal cramping
• severe diarrhea lasting more than 3 days
• temperature higher than 101.5 F (38,6 C)
• vomiting of blood

If you suspect food-borne infection, it is prudent to inform your local health department. The information that you provide could stop an outbreak that may be affecting many other individuals. The health department will ask for a list of symptoms, where and when the suspected infection occurred, and what foods were consumed.

Who should you see if you suspect that you have a case of food poisoning? Read on to learn more about which doctors and specialists are trained to diagnose food poisoning. Learn what to expect when you visit the doctor and how you can best prepare yourself. More on how to Diagnose Food Poisoning here.