The character and severity of symptoms depend on the nature
and dose of the irritant, duration of its action,
resistance of the patient, and extent of involvement of the
GI tract. Onset is sudden, with malaise, anorexia, nausea,
vomiting, abdominal cramps, diarrhea, and prostration. If
the diarrhea is intense, rectal burning and tenesmus
develop. In severe cases, discharges may contain blood and
mucus. If the fluid lost by vomiting has been excessive,
alkalosis occurs; if diarrhea has been more prominent,
acidosis is more likely. In the presence of severe
dehydration and acid base imbalance, headache and symptoms
of muscle and nervous irritability may be prominent. The
abdomen is usually distended, with tenderness more common
in the lower than in the upper quadrants.
Bed rest with convenient access to bathroom, commode, or
bedpan is desirable. Nothing is permitted by mouth so long
as nausea and vomiting persist. When they cease, light
fluids such as warm tea, barley or rice water, strained
broth, cereal, gruel, or bouillon with added salt maybe
taken. When warm liquids are tolerated, the diet may be
increased gradually to include cooked bland cereals,
gelatin, jellied consommé, simple puddings, soft-cooked
eggs, and other bland foods.
Almost all cases of food poisoning are due to Salmonella
organisms. The incubation period varies from 6 to 48 hours,
with an average of about 12 hours. Onset is abrupt, with
headache, chills, fever, muscle aches, and prostration,
accompanied by nausea, vomiting, abdominal cramps, and
severe diarrhea. In sever cases, vomitus and rectal
discharges may contain blood. Dehydration, acid-base
imbalance, anuria, and shock may develop.
The illness usually lasts 24 to 48 hours. It may be so mild
as to permit the patent to continue his usual activities;
rarely, it may fatal within 24 hours.
Diagnosis is generally easy when the patient is one of a
group that became ill after eating a certain food, and when
the symptoms are typical. Gross examination of the food may
disclose no evidence of contamination. Diagnosis is aided
by demonstration of the bacteria in the food, vomitus,
feces, blood, or urine. The organisms may persist in the
stools for 7 to 10 days following infection.
The treatment is essentially the same as mentioned in the
Ingestion of a preformed enterotoxin produced by
coagulase-positive staphylococci growing on a variety of
foods (chiefly custards, cream-filled pastry, mil,
processed meat, and fish), causes the disease. It is
probably the most common type of food poisoning and is
mainly spread by food handlers with staphylococcal skin
The incubation period is usually 2 to 4 hours after
ingestion of food containing enterotoxin. Onset is abrupt,
with nausea, vomiting, abdominal cramps, diarrhea, and
occasionally headache and fever. The attack is short in
duration, most often lasting only 3 to 6 hours with
complete recovery. Fatalities are rare.
The diagnosis is based on sudden onset after eating
infected food, brevity of symptoms, and rapidity of
Food poisoning can also occur after eating certain plants
and animals containing naturally occurring poison.
Mushroom poisoning symptoms begin within a few minutes to
two hours after ingesting. They consist of salivation,
sweating, vomiting, abdominal cramps, diarrhea, thirst,
collapse, coma, and occasionally convulsions.
Immature or sprouting potato poisoning symptoms occur
within a few hours and consist of nausea, vomiting,
abdominal cramps, diarrhea, and a sense of constriction in
the throat. Practically all victims recover.
Fish poisoning symptoms develop immediately or within 30
hours of ingestion and include numbness of the limbs,
nausea, vomiting, diarrhea, abdominal pain, joint aches,
chills, fever, sweating and painful urination. The severity
of the attacks varies greatly and to some extent depends on
the fish involved.
Chemical poisoning can be caused by eating unwashed fruits
and vegetables sprayed with arsenic, lead, or organic
insecticides, acidic liquids served in lead-glazed pottery,
or food stored in cadmium-lined containers. Severity
depends on the amount of chemical ingested.
The diagnosis is based on the clinical picture and history
of ingestion of the offending agent. Bacterial food
poisoning should be differentiated by careful tasting of
Absolute bed rest is mandatory. Little is to be gained by
giving an emetic if there has been violent vomiting or
diarrhea or if symptoms appear several hours after the food
has been ingested. Otherwise, the bulk of the poison should
be removed by gastric lavage.