Introduction to Food Allergy
Food allergy symptoms can cause troublesome. Even a small amount of food is sufficient to trigger food allergy symptoms. Food allergy can cause life-threatening reaction called anaphylaxis. In children the incidence of food allergy is about 6 to 8 percent. In adult the incidence is around 3 percent. There is no cure for food allergy but in some children food allergy may disappear when they grow older.
Symptoms of Food Allergy
Symptoms of food allergy can ranges from mild allergic reaction to severe allergic reaction. It can even cause anaphylaxis. Usually food allergy symptoms develop within a few minutes to two hours after eating the offending food.
The most common symptoms include:
- Tingling sensation or itching in and around the mouth
- Swelling of the lips, tongue, face, throat or other parts of the body
- Hives, itching or eczema
- Cough, wheezing or trouble breathing
- Nasal congestion
- Abdominal pain, nausea, vomiting, diarrhea
- Dizziness, lightheadedness or fainting
Anaphylaxis: Food allergy can cause anaphylaxis. Signs and symptoms of anaphylaxis include:
- Respiratory distress
- A swollen throat or the sensation of a lump in your throat
- Shock with a severe drop in blood pressure
- Rapid pulse
- Dizziness, lightheadedness or loss of consciousness
Anaphylaxis is a medical emergency treatment. Emergency treatment with intramuscular epinephrine/adrenaline is crucial for survival of patients..
Causes of Food Allergy
Common foods that can cause allergic reaction in adult include:
Common foods that can cause allergic reaction in children include:
Risk factor for Food allergy
- Family history of Allergy. Family history of some form of allergies like asthma, eczema, urticaria, allergic rhinitis in any members is a risk factor.
- If you are suffering from food allergy to one of the food items. If you’re already allergic to one food, then you are at risk of developing food allergy to other foods.
- Age. Overall food allergies are more common in children. Food allergy may disappear when the child grow older. In most of cases of food allergy to eggs, milk, soy and wheat in children may resolved automatically when they grow older. But allergy to shellfish and nuts may remain lifelong.
- Asthma. Asthma and food allergy can occur together. In such patient both food allergy and asthma symptoms are more likely to be severe.
Diagnosis of Food Allergy
Till date there is no ideal test for food allergy. A physician should consider the following:
- Symptoms. Tell physician /allergist, the symptoms you are experiencing. Tell about the possible food items, eating of which lead to start of your symptoms. Tell him when this symptoms start occurring, how much time the symptoms last and how you get relief.
- Family history of allergies. Tell any family members are suffering from any form of allergic disorders or not.
- A physical examination. To find out any urticarial lesion in the body and to exclude other cause of similar symptoms.
- A skin prick test. A skin prick test using food allergen can be performed. A positive prick test is only indicate that the people is sensitized to particular food allergen tested.
- A blood test. A blood test can performed to measure the allergen specific immunoglobulin E (IgE).
- Elimination diet. This can be done by first eliminating the suspected food items for 2 weeks then reintroducing the food items one by one to see when the symptoms return back.
- Oral food challenge. Here the physician will give a small but gradually increasing amount of food to see whether the symptoms are occurring or not.
Treatment of Food Allergy
Avoidance is the best preventive measure. However an individual may unknowingly come in contact with the food and lead to allergic reaction.
For mild to moderate allergic reaction: over-the-counter or prescribed antihistamines are helpful.
For severe allergic reaction: If there is severe reaction or anaphylaxis one must inject adrenaline/ epinephrine in appropriate dosage.
Ongoing Research on Food Allergy Treatment
- Anti-IgE monoclonal antibody therapy
- Oral immunotherapy
- Early exposure to allergenic food
In a study Researchers found that high-risk children who regularly consumed peanut protein in the form of peanut butter or peanut-flavored snacks, were found 70 to 86 percent less likely to develop peanut allergy.
Prevention of Food Allergy
Avoidance of the offending food is the best way to prevent food allergy. A person with food allergy must be cautious when eating in a restaurants and in social events.
If you have food allergy, then follow these steps:
- Know what you’re eating and drinking. Always read the food labels.
- If you have already had a severe reaction/anaphylaxis, wear a medical alert bracelet or necklace that lets others know that you have a food allergy.
- Have an action plan ready. Always have your epinephrine /adrenaline autoinjector with you.
- Be careful while eating at restaurants.
- Plan your meals and snacks before leaving home.
If your child has food allergy, you must follow few steps to ensure your child is safe:
- Always notify key people about the child’s food allergy.
- Explain food allergy symptoms to persons who spend time with the child.
- Have a written action plan.
- Have your child wear a medical alert bracelet or necklace.
Common conditions that mimic food allergy
- Lactase deficiency / lactose intolerance
- Food poisoning
- Celiac disease. sometimes called to as a gluten allergy
- Sensitivity to food additives.eg sulfites used in dried fruit, canned goods
- Histamine toxicity from certain not refrigerated fish