Chinese restaurant syndrome is a collection of symptoms that some people experience after eating Chinese food. A food additive called monosodium glutamate (MSG) has been implicated, but it has not been proved to be the substance that causes this condition.

In 1968, reports of a series of reactions to Chinese food were first described. MSG was reported to cause these symptoms, but subsequent research produced conflicting data. Many studies were performed, but a majority failed to show a connection between MSG and the symptoms that some people describe after eating Chinese food. For this reason, MSG continues to be used in some meals. However, it is possible that some people are particularly sensitive to food additives, and MSG is chemically similar to one of the brain's most important neurotransmitters, glutamate.

• Headache
• Flushing
• Sweating
• Sense of facial pressure or swelling
• Numbness or burning in or around the mouth
• Chest pain

Chinese restaurant syndrome is usually diagnosed based on the symptoms. The health care provider may ask the following questions as well:

• Have you eaten Chinese food within the past 2 hours?
• Have you eaten any other food that may contain monosodium glutamate within past 2 hours?

The following signs may also be used to aid in diagnosis:

• Abnormal heart rhythm observed on an electrocardiogram
• Rapid heart rate
• Decreased air entry into the lungs

Treatment will depend upon the symptoms. Most -- such as headache or flushing -- need no treatment.

Life-threatening symptoms may be similar to any other severe allergic reaction and require immediate medical attention. These include the following:

• Swelling of the throat
• Chest pain
• Heart palpitations
• Shortness of breath

Most people recover from mild cases of Chinese restaurant syndrome on their own. Their prognosis is excellent.

People who have experienced life-threatening reactions need to be extremely cautious about what they eat and should always carry medication prescribed by their doctor for emergency treatment.

If you experience any symptoms such as shortness of breath, heart palpitations, chest pain, or swelling of the lips or throat, go to the nearest emergency room immediately.