Its all about allergies

What is an Allergy?
The topic of allergies has become routine in our lives, and certainly most everyone has an idea of what an allergy is. Allergies are so common a subject in fact, it seems acceptable to discuss your allergies at a cocktail party with strangers.

An allergy is an abnormal reaction by a person's immune system against a normally harmless substance. A person without allergies would have no reaction to this substance, but when a person who is allergic encounters the trigger, the body reacts by releasing chemicals which cause allergy symptoms. However, just because there is a cause and effect between exposure to a substance and the development of symptoms does not always mean that a person is allergic to that substance. For example, medications have known and expected side effects; a person experiencing one of these side effects is not necessarily allergic to that medication.

Learn about:

* Nasal Allergies/Hay Fever
* Skin Allergies
* Food Allergies
* Drug and Medicine Allergies
* Insect Allergies

What is Happening During an Allergic Reaction?

During an allergic process, the substance responsible for causing the allergy, or allergen, binds to allergic antibodies present on allergic cells in a person's body, including mast cells and basophils. These cells then release chemicals such as histamine and leukotrienes, resulting in allergic symptoms.

Watch a video demonstrating the allergic response.
How do Allergies Start?

The allergic person can make allergic antibodies, or IgE, against a variety of allergens, including pollens, molds, animal danders, dust mites, foods, venoms and medications. This occurs through a process called sensitization, where a person’s immune system is exposed to enough of the allergen to make the body produce allergic antibodies to that substance.

With later exposures, that same allergen binds to its corresponding IgE on allergic cells, and the body reacts with symptoms of allergies. Allergic symptoms can vary somewhat with the type of allergen and route of exposure (airborne pollen exposure may cause different symptoms than eating a food to which you are allergic).

Learn how to avoid allergic triggers and avoid specific food allergens.
When and Why do People Develop Allergies?

It is unknown why some people develop allergies and some don’t. Allergies seem to run in families, and in some cases family members can share allergies to specific foods or medications. It appears that the allergic response was once meant to protect the body against parasitic infections, although now seems to be an abnormal response to non-infectious triggers.

Allergies can occur at any time during our lives, but are more common to occur during childhood or young adulthood.









Most everyone has an idea of what an allergy is. Allergies are so common, in fact, that it seems acceptable to discuss allergy symptoms at a cocktail party with perfect strangers.

An allergy is an abnormal reaction by a person's immune system to a normally harmless substance. A person without allergies would have no reaction to this substance, but when a person who is allergic encounters the trigger, the body reacts by releasing chemicals which cause allergy symptoms.

Find out more about what happens during an allergic reaction.

In children, allergic disease first occurs as atopic dermatitis (eczema) or food allergies. Children with atopic dermatitis are then at an increased risk of developing allergic rhinitis and asthma; both are more likely to occur in school-age children.

Typically, atopic dermatitis goes away by adulthood, as do many types of food allergies. Allergic rhinitis and asthma, however, most often start during the adolescent, teenage and young adult years, and are likely to persist throughout a person’s life. The severity of allergic symptoms, however, may wax and wane, and even temporarily disappear during a person’s life.
Atopic Dermatitis
This is typically the first sign of allergies and is seen in 10 to 20% of all children, frequently during infancy. Atopic dermatitis, or eczema, is characterized by itching, with rash formation at the sites of scratching. The rash is typically red and dry, may have small blisters, and can flake and ooze over time.

In infants and very young children, this rash involves the face (especially the cheeks), chest and trunk, back of the scalp and may involve the arms and legs. This distribution reflects where the child is able to scratch, and therefore usually spares the diaper area. The location of the rash changes in older children and adults to classically involve the skin in front of the elbows and behind the knees. Food and environmental allergies have been shown to worsen atopic dermatitis.

Find out more about:

* Basics of Atopic Dermatitis
* Treatment of Atopic Dermatitis

Food Allergies
Food allergies can occur at any age. Almost all people with food allergies will have a skin symptom, such as hives, swelling, itching or redness of the skin, as a result of eating the culprit food. These symptoms typically occur within a few minutes of eating the food in question, although they can be delayed up to a couple of hours.

Other symptoms of food allergies can include nausea, vomiting, stomach aches, diarrhea, breathing difficulties (asthma symptoms), runny nose, sneezing, and lightheadedness. In some cases, children can experience a severe allergic reaction, called anaphylaxis, which can be life-threatening.

Find out more about:

* Basics of Food Allergies

Nasal Allergies
Allergic rhinitis occurs in up to 30% of adults and up to 40% of children. Symptoms of allergic rhinitis include sneezing, runny nose, itchy nose and eyes and nasal congestion. Some people may also experience post-nasal drip, allergic shiners (dark circles under the eyes), and a line across the nasal bridge from an upward rubbing of the palm of the hand on the nose, a sign called the “allergic salute.”

Find out more about:

* Basics of Allergic Rhinitis
* Treatment of Allergic Rhinitis

Asthma
Allergies are a major cause of asthma, a condition that occurs in about 8% of all people. Though it can occur at any age, it is most often seen in males in the pre-teen years and in females in the teenage years; asthma is the most common chronic disease in children and young adults. Sometimes asthma is difficult to diagnose in very young children, and may require a physician who is an asthma specialist.

Symptoms of asthma may include:

* Coughing -- This can be the only symptom in some people who have “cough-variant asthma.” The cough is often dry, hacking, and may be worse with allergic triggers and after exercise. The cough may only be present at night. Cold air may also trigger this symptom.

* Wheezing -- This is a high-pitched, musical-like sound that can occur with breathing in and out in people with asthma. Wheezing usually occurs along with other asthma symptoms, may get worse with exercise and with allergic triggers.

* Shortness of breath -- Most people with asthma feel as if they’re not getting enough air at times, particularly when they are physically exerting themselves or when an allergic trigger is present. People with more severe asthma have shortness of breath at rest or wake-up with this symptom during the night.

* Chest tightness -- Some people describe this as a sensation that someone is squeezing or hugging them. Children may say that their chest hurts or feels “funny.”

Many asthmatics have symptoms with exercise; this does not necessarily mean that their asthma is severe or uncontrolled.








Allergy Diagnosis
Symptoms of allergic diseases can certainly give strong hints that a person is indeed suffering from allergies. However, in most cases, various tests are required to confirm a diagnosis. Testing depends on the type of allergic disease in question.
Atopic Dermatitis
There is no laboratory test that can be used to diagnose atopic dermatitis. Instead, a physician must examine a patient and review the history of her symptoms.

There are three criteria that must be present in order to diagnose atopic dermatitis:

* Allergies -- The person must have allergies (at least one positive skin test) and/or a family history of allergic diseases in close relatives. There may be rare cases in which a person has atopic dermatitis without evidence of allergies.

* Itching -- The patient must have itching and scratching in order for the rash to occur. If the skin or areas of the rash do not itch or have not been scratched, then the person does not have atopic dermatitis.

* Eczema -- Eczema refers to the appearance of the rash in patients with atopic dermatitis; it also occurs in those with other skin diseases. The rash appears red, with small blisters or bumps. These may ooze or flake with further scratching. Over the long-term, the skin appears thickened and leathery.

In most cases, people with atopic dermatitis should have skin testing performed to aeroallergens (pollens, molds, pet dander and dust mite) as well as to common food allergens. Avoiding allergic triggers is an important step in the treatment of atopic dermatitis.

Find out more about:

* Basics of Atopic Dermatitis
* Treatment of Atopic Dermatitis

Food Allergies
The diagnosis of food allergies is made when typical symptoms occur after eating a specific food and a patient receives a positive result after undergoing an allergy test to the food in question. Testing for the allergic antibody is best accomplished with skin testing, although can be done with a blood test as well.

The blood test, called a RAST, is not quite as good of a test as skin testing, but it can be helpful in predicting if a person has outgrown a food allergy. This is especially true since, in many cases, the skin test can still be positive in children who have actually outgrown the food allergy.

If the diagnosis of food allergy is in question despite testing, an allergist may decide to perform an oral food challenge. This involves having a person eat increasing amounts of the suspect food, over many hours, under close medical supervision. Given the potential for life-threatening allergic reactions, this procedure should only be performed by a physician experienced in the diagnosis and treatment of allergic diseases.

Find out more about:

* Basics of Food Allergies

Nasal Allergies
In many cases, allergic rhinitis is diagnosed when a person has convincing symptoms and physical exam findings consistent with this disease. However, in order for allergic rhinitis to be properly diagnosed, allergy testing is needed. Positive allergy tests are required to diagnose allergic rhinitis; negative allergy testing suggests non-allergic rhinitis. While allergy testing can be accomplished with skin testing or blood tests (RAST), skin testing is still the preferred method of testing.

Find out more about:

* Basics of Allergic Rhinitis
* Treatment of Allergic Rhinitis

Asthma
The diagnosis of asthma is suggested by the presence of asthma symptoms; however, spirometry is needed to make a firm diagnosis. Spirometry can easily be performed in people 5 years and older. It may show a specific pattern in a person with asthma, which can make the diagnosis more concrete. For example, someone with asthma may display a certain increase in lung function after using a bronchodilator, such as Albuterol.

If the diagnosis of asthma is still in question despite performing spirometry, asthma specialists can perform additional tests to determine if a person has asthma. These include bronchoprovocation (causing a drop of lung function with the inhalation of certain chemicals, such as methacholine) and measurements of markers of inflammation in exhaled air, sputum, blood and urine.








Allergy Relief
The treatment of allergies is dependent on the type of allergic disease in question. Often, allergy testing can aid in the treatment of allergies through allergen avoidance.
Atopic Dermatitis
The treatment of atopic dermatitis involves three major components:

* Avoidance of triggers
* Maintaining good skin care
* Use of appropriate medications when needed

Topical steroid creams are the preferred therapies for worsening of atopic dermatitis. Other options, for when symptoms are severe, include topical calcineurin inhibitors (such as Elidel and Protopic) and oral steroids. Sometimes, the use of oral antibiotics is needed if there is a skin infection accompanying the atopic dermatitis.

Find out more about:

* Treatment of Atopic Dermatitis
* Elidel and Protopic for the Treatment of Atopic Dermatitis

Food Allergies
The primary treatment of food allergies involves avoidance of the specific food to which a person is allergic. If the culprit food is accidentally eaten, aggressive treatment of the subsequent reaction with antihistamines and epinephrine may be necessary. Being prepared to recognize and treat an allergic reaction from food allergies may be the most important aspect of the treatment of food allergies.

Find out more about:

* Treatment of Food Allergies

Nasal Allergies
There are, in general, three options for the treatment of allergic rhinitis:

* Avoidance of triggers
* Medications
* Allergy shots

Avoidance of allergic triggers is always the primary treatment method for allergic rhinitis. This form of treatment essentially costs nothing and has no side effects; however, avoidance of triggers is not always possible. Pet and house dust mite avoidance is possible; avoidance of airborne pollen and mold spores is not.

There are numerous medications available for the treatment of allergy symptoms. In general, a medication that works particularly well for one person may not work for another, especially when the allergy symptoms are different. Medication options include nasal steroids and nasal antihistamines, oral antihistamines, oral decongestants and oral antileukotrienes, such as Singulair (montelukast).

When medications fail to adequately control allergy symptoms and avoidance of the trigger is not easy or possible, allergy shots are another treatment option. This treatment consists of a series of injections containing small amounts of the substances to which a person is allergic. After a course of allergy shots, 80 to 90% of patients have less allergy symptoms and, in many cases, allergy symptoms are completely resolved.

Find out more about:

* Avoidance of Allergy Triggers
* Treatment of Allergic Rhinitis
* Allergy Shots for Allergic Rhinitis

Asthma
In general, there are 2 types of asthma medications: rescue and controller medicines. Most asthmatics require both medications. Rescue medicines are those that are taken as needed. This means that these medicines should be carried by the person with asthma, since an asthma attack can never be predicted. Rescue medicines help relax the muscle around the airways for a few hours, but they do not help the inflammation and swelling of the airways.

Controller medicines are those medicines that are taken every day (sometimes multiple times a day), regardless of asthma symptoms. These medicines are taken all of the time in order to control the inflammation and swelling of the airways. This leads to less irritation and constriction of the muscles around the airways and, therefore, less asthma symptoms. These medicines usually take a few days to weeks to start working. A person with asthma then notices that less and less rescue medicine is needed.









The ultimate goal of allergy treatment is preventing the symptoms from occurring in the first place. This usually includes learning how to avoid the allergen, whether it be pets, foods, insects or even certain chemicals. Preventing the development of allergies, asthma and food allergies in young children also is possible.
Prevention of Allergies, Asthma and Food Allergies in Children
The goal of any family prone to allergies is to prevent the development of allergies in their child. Various strategies have been shown to reduce the development of allergies and asthma, as well as to prevent or delay the onset of food allergies in children.

Prevention of Allergies and Asthma in Children

Prevention of Food Allergies in Children
Avoidance of Indoor Allergens
Common indoor allergens, including pet dander and dust mites, are typically year-round triggers of allergy and asthma symptoms. Therefore, avoidance of these triggers is an important aspect of the prevention and treatment of allergies.

Avoidance of Dust Mite and Cockroach Allergens

Avoidance of Cat Allergen

Avoidance of Dog Allergen
Avoidance of Outdoor Allergens
Avoidance of outdoor allergy triggers, such as plant pollens and molds, is difficult, as these allergens are blowing around in the air. There are some measures that can be taken, however, to minimize exposure to pollens and outdoor molds.

Avoidance of Pollens

Avoidance of Molds
Food Allergy Avoidance
Avoidance of the specific food trigger is the main treatment of food allergy. Unfortunately, it's sometimes next to impossible to avoid certain foods, such as peanuts, which are very common. Therefore, a person with food allergies needs to closely follow a diet free from the culprit food, while also knowing how to cope with an allergic reaction.

Basics of Food Avoidance

Specific Food-Avoidance Diets
Avoidance of Biting and Stinging Insects
People who are allergic to biting and stinging insects should take measures to avoid future stings and bites, such as avoiding walking barefoot outdoors, exterminating known insect infestations, not looking or smelling like a flower, and the judicious use of insect repellants. Learn more about the avoidance of specific types of insects.