Food allergy

Description

Food allergy is an immune-mediated adverse reaction to a particular food. For some of those affected, consuming and swallowing even a small amount of a certain food can cause symptoms such as skin rash, nausea, vomiting, cramps and diarrhea.

Because the body reacts to a substance that is generally harmless, this type of allergic reaction is often called a hypersensitivity reaction. In rare cases, a severe immune response can lead to life-threatening symptoms called anaphylaxis or anaphylactic shock.

Although about 25-30% of people believe that the body reacts violently to a certain food, only about 2.5% of adults and about 6-8% of children, and mostly those under the age of 6 have true food allergies.

The rest have a condition known as a food intolerance – an adverse reaction to food that does not affect the immune system.

It is easy to confuse a food intolerance with an allergy because the symptoms can be very similar. With food intolerance, however, the sufferer usually only experiences mild symptoms such as an upset stomach.

A typical example of intolerance is lactose intolerance, a condition in which a person’s body lacks a certain enzyme needed to break down milk proteins.

The result is diarrheal feces, gas, nausea after consuming dairy products such as milk and cheese. Another example of food intolerance is a reaction to monosodium glutamate, a white additive used to improve the taste of food.

What are the symptoms?

Symptoms may appear immediately or within two minutes of ingestion, but the reaction may be slower and take several days to appear with its typical clinical picture. Sometimes the symptoms subside quickly only to recur after 3-4 hours.

The most common symptoms are:

• Itching of the skin followed by the appearance of red bumps in the form of spots on the skin;
• Swelling of the lips and mouth;
• Abdominal cramps;
• Nausea;
• Vomiting;
• Diarrhea;

Other possible symptoms are:

• Itchy and watery ears;
• Runny or stuffy nose;
Symptoms of a more severe reaction may include the following:
• Shortness of breath or difficulty breathing;< br/> • Runny or stuffy nose;
• Feeling of tightness in the throat or choking;
• Fast or irregular heartbeat;
• Feeling dizzy or faint;
• Loss of consciousness;

What are the causes?

An allergic reaction occurs when the body’s immune system overreacts to a food protein.

White blood cells produce antibodies to this allergen called immunoglobulin E or IgE. When antibodies come into contact with a certain food protein, it stimulates the synthesis and release of certain chemicals called “mediators”. Histamine is an example of a mediator.

Treatment of food allergy

For localized urticaria or other mild skin reactions:

• Take a cool shower or apply cold compresses;
• Wear light clothing that does not irritate the skin;
• Rest and avoid more serious exertion;
• To relieve itching, apply calamine lotion or get antihistamines such as diphenhydramine from the pharmacy;
• Try to remain calm;
• If possible, try to identify the cause of the reaction and stop the exposure.

Medications

• Epinephrine – is used only in very severe allergic reactions /anaphylaxis/, by injecting it and acting as a bronchodilator – it expands the respiratory tubes. It also constricts blood vessels and helps normalize blood pressure. In case of a less severe allergic reaction, inhalations with epinephrine bronchodilator can be done, as in asthma.
• Diphenhydramine – suppresses the action of histamines;
• Corticosteroids – are administered intravenously to quickly control the effects of the mediators of the allergic reaction.