The signs and symptoms of food poisoning can vary depending on the type of contaminant and the severity of the illness. They may also begin within a few hours or a few weeks depending on the cause. Common symptoms are:
- Upset stomach.
- Vomiting.
- Diarrhea.
- Diarrhea with bloody stools.
- Stomach pain and cramps.
- Fever.
- Headache.
Less often food poisoning affects the nervous system and can cause severe disease. Symptoms may include:
- Blurred or double vision.
- Headache.
- Loss of movement in limbs.
- Problems with swallowing.
- Tingling or numbness of skin.
- Weakness.
- Changes in sound of the voice.
When to see a doctor
Infants and children
Vomiting and diarrhea can quickly cause low levels of body fluids, also called dehydration, in infants and children. This can cause serious illness in infants. Call your child’s health care provider if your child’s symptoms include vomiting and diarrhea and any of the following:
- Unusual changes in behavior or thinking.
- Excessive thirst.
- Little or no urination.
- Weakness.
- Dizziness.
- Diarrhea that lasts more than a day.
- Vomiting often.
- Stools that have blood or pus.
- Stools that are black or tarry.
- Severe pain in the stomach or rectum.
- Any fever in children under 2 years of age.
- Fever of 102 degrees Fahrenheit (38.9 degrees Celsius) or higher in older children.
- History of other medical problems.
Adults
Adults should see a health care provider or get emergency care if the following occur:
- Nervous system symptoms, such as blurry vision, muscle weakness and tingling of skin.
- Changes in thinking or behavior.
- Fever of 103 degrees Fahrenheit (39.4 degrees Celsius).
- Vomiting often.
- Diarrhea that lasts more than three days.
- Symptoms of dehydration — excessive thirst, dry mouth, little or no urination, severe weakness, dizziness, or lightheadedness.
In most cases, food poisoning symptoms are mild and resolve within a few days without medical treatment. However, severe cases of food poisoning can cause dehydration, organ damage, and even death, especially in vulnerable populations such as the elderly, young children, and individuals with weakened immune systems.
If you experience severe or prolonged symptoms of food poisoning, seek medical attention immediately.