Food Poisoning: Symptoms, Causes & Treatment

Food poisoning happens after eating food contaminated with harmful toxins, bacteria, viruses, or other microorganisms. It commonly causes nausea, vomiting, diarrhea, stomach pain, and fever, with symptoms often starting within hours of eating contaminated food.

Most cases of food poisoning improve within a few days with rest, plenty of fluids, and a light, easy-to-digest diet. However, severe dehydration, persistent symptoms, or illness in young children, older adults, pregnant women, or people with weakened immune systems may require prompt medical care.

Food poisoning is usually diagnosed based on symptoms and recent food intake, although blood or stool tests may be needed in more severe cases. Treatment may include hydration, dietary changes, and, in some situations, medications prescribed by a healthcare provider.

How long does food poisoning last?

Food poisoning usually lasts a few hours to a few days, depending on the cause and severity of symptoms. Medical care is recommended if symptoms do not improve within 2 to 3 days, or if signs of dehydration, dizziness, or worsening diarrhea occur.

Pregnant women, older adults, and children should see a doctor if they develop any symptoms of food poisoning, as these groups have a higher risk of complications.

Food poisoning symptoms

Symptoms of food poisoning typically occur a few hours after ingesting the contaminated food. The main symptoms include:

• General malaise
• Frequent nausea and vomiting
• Diarrhea
• Low-grade fever
• Stomach ache

More serious symptoms include dry mouth, excessive thirst, earache, or dizziness.

Online symptom checker

Enter your symptoms below if you suspect you may have food poisoning:

This symptom quiz is only a guidance tool and does not provide a diagnosis. It should not replace an assessment by a healthcare provider.

Confirming a diagnosis

In general, food poisoning is diagnosed by assessing symptoms and reviewing the foods eaten before symptoms started.

If symptoms are severe or persistent, a healthcare provider may order blood tests to check overall health and stool tests to identify the germ causing the infection.

What causes food poisoning?

Food poisoning is caused by toxins released by harmful microorganisms that can be present in food. It is most commonly caused by Staphylococcus aureus and Clostridium botulinum bacteria. However, some cases of food poisoning can also be caused by fungi.

Food poisoning can occur after eating food that has not been properly stored, handled, or prepared, or food that has passed its expiration date.

Food poisoning treatment

Food poisoning symptoms can usually be managed at home without any specific medication. According to the CDC, drinking plenty of fluids is one of the most important treatments for food poisoning because it helps prevent dehydration caused by vomiting and diarrhea.

Treatment also involves following a low-fat, low-fiber diet to support recovery, help eliminate toxins, and relieve symptoms.

Food poisoning medication

In general, the use of medication is not recommended for the treatment of food poisoning, as symptoms usually improve with increased fluid intake and a light diet.

However, if symptoms do not improve or become more serious, the doctor may prescribe pain relievers for abdominal pain, antibiotics for food poisoning caused by infection, or probiotics to help restore healthy gut bacteria. Learn more about the benefits of probiotics and how to take them.

According to the CDC, medications that relieve diarrhea should generally not be used unless recommended by a healthcare provider, as they may not be appropriate for certain types of food poisoning and can delay the elimination of some infectious organisms.

Read more about food poisoning medications that can help to speed-up recovery.

What to eat after food poisoning

If you have food poisoning, it is important to eat light, easy-to-digest foods that can help relieve symptoms and support recovery. Recommended foods include:

• Caffeine-free, sugar-free tea
• Peeled baked apple or pear
• Banana
• Boiled carrot
• Plain white rice or pasta
• Boiled potato
• Grilled or boiled chicken
• White bread with jam

It is also important to avoid foods that are harder to digest, such as tomatoes, beans, red meat, lettuce, cabbage, butter, whole milk, seeds, and strong seasonings. Processed and fatty foods should also be avoided, as they can worsen nausea, diarrhea, or stomach discomfort.

In the first few days, cooked fruits without the peel and strained fruit juices are recommended. Once diarrhea improves, vegetables can be reintroduced, preferably boiled or blended into a soup.