Food Allergy (cont.)
Food Allergy Symptoms
A person with a food allergy can have symptoms beginning as soon as 2 minutes after eating the food, but reactions may take 1 to 2 hours to appear. Occasionally, symptoms abate quickly, only to recur in 3 to 4 hours.
- The most common symptoms include the following:
- Itching of the skin followed by hives, a rash of raised, reddish bumps or wheals
- Swelling of the lips and mouth
- Belly cramps
- Other symptoms may include the following:
- Itching and watering in the eyes
- Runny or stuffy nose
- Symptoms of a more severe reaction could include the following:
- Shortness of breath or difficulty breathing
- Tightness in the chest
- Feeling of tightness or choking in the throat
- Rapid or irregular heart beat
- Feeling dizzy or light-headed
- Losing consciousness
- A severe allergic reaction can be life threatening. This severe reaction is referred to as anaphylaxis, or anaphylactic shock.
- The dizziness, lightheadedness, and loss of consciousness are due to dangerously low blood pressure, called "shock."
- An anaphylactic reaction can begin suddenly, or it may develop gradually with itchiness and swelling of the skin and throat and then progress to a severe reaction over a few hours.
- Most people get such a reaction immediately after eating the food, but in a few unusual cases the reaction occurs only after exercising following the ingestion of the food.
- Severe reactions are most often seen with allergies to nuts, fish, and shellfish, although allergy to any food can cause anaphylaxis.
- People with asthma, childhood allergies, eczema, or prior severe food allergies are especially at risk for having an anaphylactic reaction.
- MSG reaction can be mistaken for an allergic reaction.
- Symptoms of MSG reaction include the following:
- Burning sensation at the back of the neck and radiating down the arms and chest
- Tingling and numbness in the same areas
- Occasionally, difficulty breathing, especially in those with poorly-controlled asthma
- A few people experience seizures, irregular heartbeats, and anaphylaxis after the use of MSG.
- Contrary to popular beliefs, MSG has no relation to Alzheimer disease, Huntington chorea, or other chronic illnesses.
Medically Reviewed by a Doctor on 9/7/2012
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