Symptoms and treatment of Food allergy

Description

Food allergy is an immune system reaction that occurs soon after eating a certain food. Even a small amount of the allergy-causing food can trigger symptoms such as hives, swelling of the airways and digestive problems. In some people, a food allergy can cause severe symptoms or even a life-threatening reaction known as anaphylaxis.

Food allergy affects an estimated 8% of children under 5 years of age and up to 4% of adults. Although there is no cure, some children outgrow food allergies as they age.

It is easy to confuse a food allergy with a much more common reaction known as food intolerance. While bothersome, food intolerance is a less serious condition that does not involve the immune system.

Symptoms

For some people, an allergic reaction to a particular food may be uncomfortable but not severe. For other people, a food allergy reaction can be frightening and even life-threatening. Food allergy symptoms usually develop within a couple of minutes to two hours after eating the offending food. Rarely, symptoms may be delayed for several hours.

The most common food allergy symptoms include:

Tingling or itching in the mouth.
Hives, itching or eczema.
Swelling of the lips, face, tongue, and throat or other parts of the body.
Abdominal pain, diarrhea, nausea, or vomiting.
Wheezing, nasal congestion or trouble breathing.
The dizziness, lightheadedness, or fainting.

Anaphylaxis

In some people, a food allergy can trigger a severe allergic reaction called anaphylaxis. This can cause life-threatening symptoms, including:

The constriction and narrowing of the airways.
A swelling in the throat or the sensation of a lump in the throat that makes it hard to breathe.
Shock with a severe drop in blood pressure.
Rapid pulse.
Dizziness, lightheadedness or loss of consciousness.

The emergency treatment is critical for anaphylaxis. It is not treated, anaphylaxis can be fatal.

When to see a doctor

Consult a health care provider or allergist if you have a food allergy symptoms shortly after eating. If possible, consult a health care professional when the allergic reaction is occurring. This can help make a diagnosis.

Seek emergency treatment if you develop any of the symptoms of anaphylaxis, such as:

The constriction of the airways that makes it hard to breathe.
Shock with a severe drop in blood pressure.
Rapid pulse.
Dizziness or feeling light-headed.

Causes

When you have a food allergy, your immune system mistakenly identifies a specific food or a substance in food as something harmful. In response, your immune system triggers cells to an antibody known as immunoglobulin E (IgE) to recognize the allergy-causing food or substance, called an allergen.

The next time you eat even the smallest amount of that food, IgE antibodies sense. Then signal your immune system to release a chemical called histamine, as well as other chemicals into the bloodstream. These chemicals cause allergy symptoms.

The majority of food allergies are caused by certain proteins in:

Crustaceans crustaceans, such as shrimp, lobster and crab.
Peanuts.
Nuts, such as walnuts and pecans.
Fish.
The chicken eggs.
The milk of a cow.
Of wheat.
The soy.

The pollen-food allergy syndrome

Also known as oral allergy syndrome, pollen-food allergy syndrome affects many people who have hay fever. In this condition, certain fresh fruits and vegetables or nuts and spices can trigger an allergic reaction that causes the mouth to tingle or itch. In severe cases, the reaction resulting in inflammation of the throat or even anaphylaxis.

The proteins in certain fruits, vegetables, nuts, and spices cause of the reaction because they are similar to those allergy-causing proteins found in certain pollens. This is an example of cross-reactivity.

The symptoms are usually triggered by the consumption of these foods when they are fresh and raw. However, when these foods are cooked, the symptoms may be less severe.

The following table shows the specific fruits, vegetables, nuts and spices that can cause pollen-food allergy syndrome in people who are allergic to different types of pollen.

Exercise-induced food allergy

Eating certain foods can cause some people to feel itching and dizzy shortly after the start of the exercise. More severe cases may even involve hives or anaphylaxis. Not eating for a couple of hours before you exercise, and avoiding certain foods may help prevent this problem.

Food intolerance and other reactions

The food intolerance or a reaction to another substance that ate may cause the same symptoms of a food allergy do not — such as nausea, vomiting, cramps, and diarrhea.

Depending on the type of food intolerance you have, you may be able to eat small amounts of problem foods without a reaction. On the contrary, if you have a true food allergy, even a small amount of the foods that may trigger an allergic reaction.

One of the complicated aspects of diagnosis of food intolerance is that some people are susceptible not to the food itself, but to a substance or ingredient used in the preparation of food.

Common conditions that can cause symptoms confused with a food allergy include:

The absence of an enzyme needed to fully digest a food. You can't have enough of some of the enzymes needed to digest certain foods. Insufficient amount of the enzyme lactase, for example, reduce your ability to digest lactose, the main sugar in milk products. Lactose intolerance can cause bloating, cramping, diarrhea, and excessive gas.
The food poisoning. Sometimes food poisoning can mimic an allergic reaction. The bacteria in spoiled tuna and other fish also can make a toxin that causes adverse reactions.
Sensitivity to food additives. Some people have allergic reactions and digestive and other symptoms after eating certain food additives. For example, sulfites used to preserve dried fruit, canned goods and wine can trigger asthma attacks in people with sensitivity to food additives.
The toxicity of histamine. Certain fish, such as tuna or mackerel, which are not refrigerated properly and that contain high amounts of bacteria can also contain high levels of histamine that cause symptoms similar to those of food allergy. In place of an allergic reaction, this is known as the toxicity of histamine or scombroid poisoning.
The celiac disease.While celiac disease is sometimes referred to as a gluten allergy, not as a result of anaphylaxis. As a food allergy, celiac disease does not involve an immune system response, but it is the only reaction that is more complex than a simple food allergy. This course digestive condition is triggered by the consumption of gluten, a protein found in bread, pasta, crackers and many other foods containing wheat, barley or rye. If you have celiac disease and eat foods containing gluten, an immune reaction occurs that causes damage to the surface of the small intestine. This leads to an inability to absorb certain nutrients.

The celiac disease. While celiac disease is sometimes referred to as a gluten allergy, not as a result of anaphylaxis. As a food allergy, celiac disease does not involve an immune system response, but it is the only reaction that is more complex than a simple food allergy.

This course digestive condition is triggered by the consumption of gluten, a protein found in bread, pasta, crackers and many other foods containing wheat, barley or rye.

If you have celiac disease and eat foods containing gluten, an immune reaction occurs that causes damage to the surface of the small intestine. This leads to an inability to absorb certain nutrients.

Risk factors

Food allergy risk factors include:

The history of the family. You are at higher risk of food allergies whether asthma, eczema, hives or allergies such as hay fever are common in your family.
Other allergies. If you are already allergic to a food, you may be at higher risk of being allergic to another. In the same way, if you have any other types of allergic reactions, such as hay fever or eczema, the risk of having a food allergy is greater.
Age.Food allergies are more common in children, especially small children and babies. As children grow, their digestive systems mature and their bodies are less likely to react to the components of the foods that trigger allergies. Fortunately, the children tend to outgrow allergies to milk, soy, wheat and eggs. Severe allergies and allergies to nuts and shellfish are more likely to be for life.
Asthma. The asthma and allergy to foods that commonly occur together. When they do, both food allergy and asthma symptoms are more likely to be serious.

Age. Food allergies are more common in children, especially small children and babies. As children grow, their digestive systems mature and their bodies are less likely to react to the components of the foods that trigger allergies.

Fortunately, the children tend to outgrow allergies to milk, soy, wheat and eggs. Severe allergies and allergies to nuts and shellfish are more likely to be for life.

Factors that may increase your risk of developing an anaphylactic reaction include:

Having a history of asthma.
Being a teenager or young.
Delay the use of epinephrine to treat your food allergy symptoms.
Don't have hives or other skin symptoms.

Complications

Complications of food allergy can include:

Anaphylaxis. This is a life-threatening allergic reaction.
Atopic dermatitis, also known as eczema. Food allergies can cause a reaction in the skin, such as eczema.

Prevention

Early exposure

The early introduction of peanut products has been associated with a lower risk of peanut allergy. In an important study, infants of high — risk such as those with atopic dermatitis or egg allergy, or both were selected to eat or avoid peanut products from 4 to 6 months of age up to 5 years of age.

The researchers found that high-risk children who regularly consume protein of peanuts, such as peanut butter or peanut-flavored snacks, were about 80% less likely to develop a peanut allergy.

Before the introduction of allergenic foods, talk with your child's health care team about the best time to offer them.

Taking precautions

Once a food allergy has already been developed, the best way to prevent an allergic reaction is to know and avoid foods that cause signs and symptoms. For some people, this is a mere inconvenience, but for others it is very difficult. In addition, some foods, when used as ingredients in certain dishes — may be hidden. This is especially true in restaurants and in other social environments.

If you know that you have a food allergy, follow these steps:

Know what you are eating and drinking. Be sure to read food labels carefully.
If you have already had a severe reaction, wear a medical alert bracelet or necklace that lets others know that you have a food allergy in the event that you have a reaction, and you can't communicate.
Talk with your health care team about the prescription of emergency epinephrine. You may need to carry an auto-injector of epinephrine (Adrenaclick, EpiPen) if you're at risk of a severe allergic reaction.
Be careful at restaurants.Make sure your server or chef is aware that you may not eat the food that you are allergic to, and you need to be absolutely sure that the food that the end does not contain it. Also, make sure that the food is not prepared on the surfaces or in containers that contained any of the food that you are allergic to. Do not be reluctant to ask your needs. Restaurant staff members are usually more than happy to help when it is clearly understood your request.
Plan meals and snacks before you leave home. If necessary, take a cooler full of allergen-free foods when you travel or go to a event. If you or your child can't have the cake or dessert at a party, wear approved a special treatment so that no one feels left out of the celebration.

Be careful at restaurants. Make sure your server or chef is aware that you may not eat the food that you are allergic to, and you need to be absolutely sure that the food that the end does not contain it. Also, make sure that the food is not prepared on the surfaces or in containers that contained any of the food that you are allergic to.

Do not be reluctant to ask your needs. Restaurant staff members are usually more than happy to help when it is clearly understood your request.

If your child has a food allergy, take these precautions to ensure the safety of your child:

Notify key people that your child has a food allergy. Talk with the child care providers, school personnel, the parents of your child's friends and other adults who regularly interact with your child. Note that an allergic reaction can be life-threatening and requires immediate action. Make sure your child knows to ask for help right away if your child reacts to the food.
Explain the symptoms of a food allergy. Teach adults who spend time with your child about how to recognize the signs and symptoms of an allergic reaction.
Write a plan of action. Your plan should describe how to care for your child when your child has an allergic reaction to the food. Provide a copy of the plan to the school nurse of his son and others who care for and supervise your child.
Have your child wear a medical alert bracelet or necklace. This alert lists your child's allergy symptoms and explains how others can provide first aid in case of emergency.

Diagnosis

There is no perfect test is used to confirm or rule out a food allergy. Your healthcare team will consider some factors before making a diagnosis. These factors include:

Their symptoms. Give your care team for a detailed history of your or your child's symptoms — which foods, and how much, seem to cause problems.
Your family history of allergies. We also share information about members of your family who have allergies of any kind.
A physical exam. A careful examination can often identify or rule out other medical problems.
A skin test.A skin test can determine if you can react to a particular food. In this test, a small amount of the suspected food is placed on the skin of their forearm or on the back. A doctor or other health care professional, then punctures the skin to allow a small amount of the substance below the surface of the skin. If you are allergic to a particular substance that is being tested, it develops a bump or reaction. However, a positive reaction to this test alone is not sufficient to confirm food allergy.
A blood test.A blood test can measure your immune system's response to certain foods by measuring the allergy-related antibody known as immunoglobulin E (IgE). For this test, a sample of blood taken in by your health care professional for the office is sent to a medical lab. It's going to be tested by the food that could have caused an allergic reaction.
Elimination diet.You can order to eliminate the suspected food for a week or two, and then add the food items back into your diet one at a time. This process can help to link symptoms to specific foods. However, elimination diets are not impregnable. An elimination diet can't tell if your reaction to a food is a true allergy in place of a food sensitivity. Also, if you have had a severe reaction to a food in the past, an elimination diet may not be safe.
Oral food challenge. During this test, which is performed in a professional of the health of the office, it will give small, but the increase in the quantities of food that it is suspected that the cause of your symptoms. If you do not have a reaction during this test, you may be able to include this food in your diet again.

A skin test. A skin test can determine if you can react to a particular food. In this test, a small amount of the suspected food is placed on the skin of their forearm or on the back. A doctor or other health care professional, then punctures the skin to allow a small amount of the substance below the surface of the skin.

If you are allergic to a particular substance that is being tested, it develops a bump or reaction. However, a positive reaction to this test alone is not sufficient to confirm food allergy.

A blood test. A blood test can measure your immune system's response to certain foods by measuring the allergy-related antibody known as immunoglobulin E (IgE).

For this test, a sample of blood taken in by your health care professional for the office is sent to a medical lab. It's going to be tested by the food that could have caused an allergic reaction.

Elimination diet. You can order to eliminate the suspected food for a week or two, and then add the food items back into your diet one at a time. This process can help to link symptoms to specific foods. However, elimination diets are not impregnable.

An elimination diet can't tell if your reaction to a food is a true allergy in place of a food sensitivity. Also, if you have had a severe reaction to a food in the past, an elimination diet may not be safe.

Treatment

A way to prevent an allergic reaction is to avoid the foods that cause the symptoms. However, despite your best efforts, you can get in contact with a food that causes a reaction.

For a minor allergic reaction, antihistamines prescribed or which are available without a prescription, can help to reduce symptoms. These medications can be taken after exposure to an allergy-causing foods to help alleviate the itching, or hives. However, antihistamines can not treat a severe allergic reaction.

For a severe allergic reaction, you may need an emergency injection of epinephrine and a trip to the emergency room. Many people with allergies carry an auto-injector of epinephrine (Adrenaclick, EpiPen). This device is a combination of syringe and concealed needle that injects a single dose of medication when pressed against your thigh.

If you have been prescribed an auto-injector of epinephrine:

Make sure that you know how to use the injector. Also, make sure that the people closest to you know how to give the medication — if they're with you in an anaphylactic emergency, it could save your life.
Carry it with you at all times. It may be a good idea to keep an extra injector in your car or in your desk at work.
Always be sure to replace epinephrine prior to its expiration date, or it may not work properly.

Emerging treatments

Research continues to find better treatments to reduce the symptoms of food allergy and to prevent allergy attacks. However, there is currently no proven treatment that can prevent or relieve the symptoms completely.

The Food and Drug Administration recently approved omalizumab (Xolair) to help reduce allergic reactions to multiple foods. Omalizumab is a type of medicine called a monoclonal antibody. This medication is approved for certain adults and children 1 year of age or older.

Omalizumab does not prevent all allergic reactions to food. Also, it has not been tested to see if people with food allergy can add allergens from foods in their diets. In its place, omalizumab can be used as a preventive measure. Regular injections of omalizumab can reduce the allergic reaction to a food, if small amounts of food allergens are eaten by mistake.

The first immunotherapy oral drug, Peanut (Arachis hypogaea) Allergen Powder-dnfp (Palforzia), has also been approved for the treatment of children with ages from 4 to 17 years of age with a confirmed peanut allergy. This medicine is not recommended for people with uncontrolled asthma or certain conditions, including esophagitis eosinophilic.

The additional treatment, which is currently being studied as treatments for food allergy are the immunotherapy oral and sublingual immunotherapy. With these treatments, which are exposed to small doses of your food allergen. You swallow the small dose, the dose will be placed under the tongue. The dose of the allergy to the reflection of the food is increased gradually.

Lifestyle and home remedies

One of the keys to prevent an allergic reaction is to completely avoid the food that causes your symptoms.

Don't assume.Always read food labels to ensure that they do not contain an ingredient that you are allergic to. Even if you think that you know what is in a food, check the label. Ingredients sometimes change. Food labels are required to clearly list if the food products containing common allergens in food. Read food labels carefully to avoid the most common sources of food allergens: milk, eggs, peanuts, tree nuts, fish, shellfish, soy, and wheat.
In case of doubt, say no, thank you.At restaurants and social gatherings, you're always taking a risk that you may eat foods that you are allergic to. Many people do not understand the severity of an allergic reaction to a food reaction and you may not realize that a small amount of a food can cause a severe reaction in some people. If you have any reason to believe that a food may contain something you're allergic, don't eat it.
Involve caregivers.If your child has a food allergy, with the help of family members, babysitters, teachers, and other caregivers. Make sure that you understand how important it is for your child to avoid the allergy-causing foods, and they know what to do in case of an emergency. It is also important to let caregivers know what steps can be taken to prevent a reaction in the first place, as on a careful washing of hands and cleaning of any surfaces that might have come in contact with allergens food.

Don't assume. Always read food labels to ensure that they do not contain an ingredient that you are allergic to. Even if you think that you know what is in a food, check the label. Ingredients sometimes change.

Food labels are required to clearly list if the food products containing common allergens in food. Read food labels carefully to avoid the most common sources of food allergens: milk, eggs, peanuts, tree nuts, fish, shellfish, soy, and wheat.

In case of doubt, say no, thank you. At restaurants and social gatherings, you're always taking a risk that you may eat foods that you are allergic to. Many people do not understand the severity of an allergic reaction to a food reaction and you may not realize that a small amount of a food can cause a severe reaction in some people.

If you have any reason to believe that a food may contain something you're allergic, don't eat it.

Involve caregivers. If your child has a food allergy, with the help of family members, babysitters, teachers, and other caregivers. Make sure that you understand how important it is for your child to avoid the allergy-causing foods, and they know what to do in case of an emergency.

It is also important to let caregivers know what steps can be taken to prevent a reaction in the first place, as on a careful washing of hands and cleaning of any surfaces that might have come in contact with allergens food.

Coping and support

A food allergy can be a source of constant concern that affects the life in the home, school and work. Daily activities that are easy for most families, such as shopping and meal preparation can become in times of stress to families and caregivers who live with food allergies.

Keep these strategies in mind to help you manage your or your child's food allergy-related stress:

Connect with others.The opportunity to discuss food allergies and the exchange of information with others who share your concerns can be very useful. Many internet sites and non-profit organizations offer information and forums for the discussion of food allergies. Some are specifically for parents of children with food allergies. The Food Allergy Research and Education website can direct you to support groups, and events in your area.
Educate those around you. Make sure that the family members and caregivers, including nannies and staff of the school, they have a full understanding of your child's food allergy.
Address bullying. Sometimes the children are bullied in school because of their food allergies. Discussing your child's allergies with the staff of the school greatly reduces the risk of your child being a target of bullying.

Connect with others. The opportunity to discuss food allergies and the exchange of information with others who share your concerns can be very useful.

Many internet sites and non-profit organizations offer information and forums for the discussion of food allergies. Some are specifically for parents of children with food allergies. The Food Allergy Research and Education website can direct you to support groups, and events in your area.

Preparing for your appointment

Because appointments can be brief, and because there is often a lot of ground to cover, it is a good idea to be well prepared. Here's some information to help you prepare and what to expect.

Make a note of the symptoms that I had, including those that may seem unrelated to the reason for which you scheduled the appointment.
Write down key personal information, including any major stresses or recent life changes.
Make a list of all the medicines, vitamins, and supplements you are taking.
Have a family member or friend along, if possible. Sometimes it can be difficult to remember all the information provided to you during an appointment. Someone who accompanies you may remember something that you missed or forgot.
Write questions to ask their care team.

Your time is limited, so preparing a list of questions will help you to make the most of your time together. A list of questions from most important to least important in case time runs out. Some basic questions to ask include:

Is my condition likely caused by a food allergy or other reaction?
What kinds of tests do I need?
Is my condition likely temporary or long-term?
What types of treatment are available, and which do you recommend?
What are the alternatives to the primary approach you're suggesting?
I have these other health conditions. How can I best manage these conditions?
Are there restrictions in the diet should I follow?
You should see a specialist? What will that cost, and will my insurance cover seeing a specialist?
Is there a generic alternative to the medicine you're prescribing me?
Do you have any printed material that I can take my house? What sites do you recommend to visit?

If your child sees the doctor for a food allergy, you can also ask the following:

Is my child likely to overcome this type of allergy?
There are alternatives to the food or the foods that trigger my child's allergy symptoms?
How can I help support my child with a food allergy safe in school?

In addition to the questions that you've prepared to ask your doctor, do not hesitate to ask questions during your appointment.

What to expect from your doctor

Your doctor may ask you some questions. Be prepared to answer them you can save your time to go through any of the points that you want to devote more time. You may ask:

When did you begin experiencing symptoms?
How severe were your symptoms?
How much time is necessary that the symptoms appear after eating the food that you suspect that you are allergic to?
Did you take any non-prescription allergy medications such as antihistamines, and if so, does it help?
Does your reaction always seem to be triggered by a certain food?
The amount of food we ate before the reaction?
It was the food that causes the reaction raw or cooked?
Do you know how the food was prepared?
What, if anything, seems to improve your symptoms?
What, if anything, appears to worsen your symptoms?

What you can do in the meantime

If you suspect that you have a food allergy, avoiding exposure to food for full until your appointment. If you eat the food and have a mild reaction, over-the-counter antihistamines can help relieve the symptoms. If you have a more severe reaction, and the symptoms of anaphylaxis, seek emergency help.