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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 1-2 hours to appear. Occasionally, symptoms abate quickly, only to recur in 3-4 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
  • Nausea
  • Vomiting
  • Diarrhea

• 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, light-headedness, 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
    • Headache
    • Nausea
    • 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.