Archive for the 'Allergy Shots' Category

Allergy Shots Part 5: Children And Allergy Shots

June 11, 2010

Although allergy shots are effective at any age, I generally do not consider allergy shots as a treatment option until after 7 years of age.  The reason for this is that I think prior to that age it is difficult for children to fully understand why they are getting weekly shots and I fear that the potential psychological trauma may out way the benefits.   

There is reason to believe that the earlier allergy shots are started the more significant the benefits.  Allergy shots may prevent the development of new allergies in children who are allergic to one or two allergens.  It is not unusual for a child to first develop allergies to tree pollen and then over time develop allergies to other pollens or dust mite.  Alternatively, a child can first develop allergies to dust mites or cockroach and then over time develop various seasonal pollen allergies.  Allergy shots may also prevent the development of asthma in children who are receiving shots for nasal allergies.

Note: The content of this blog is for informational purposes only and is not meant as specific medical advice for a specific person.   If you have a medical problem, please contact your doctor.

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Allergy Shots Part 4: What Results Can I Expect?

June 10, 2010

The main positive affects of allergy shots are not felt until maintenance is reached.  It is generally possible however to get an idea of how effectively a patient is becoming desensitized by noting how they respond to the allergy shots.  If a patient is able to tolerate increasing doses of allergens without having significant local reactions at the site of the injections and without having more generalized allergic reactions to the shots, then that patient is becoming desensitized.  Maintenance doses are large doses of allergen that would definitely result in significant allergic reactions if administered to an allergic person prior to undergoing the build up desensitization phase.

Each person clinically responds to allergy shots in a slightly different way.  The best case scenario is complete desensitization with elimination of the allergic response to the allergen.  The best example of this is a patient with tree pollen allergy who comes in for a monthly maintenance shot in early May and has no allergy symptoms and is on no medications and asks me if the tree pollen season has started.  I am always thrilled when this happens since by early May in New York, people with tree pollen allergy have usually already been suffering with symptoms for several weeks.  Some people have this kind of response.  Others have a less complete desensitization in that they still have some symptoms, though less severe than before starting allergy shots and more easily controlled with fewer medications.

Unfortunately, it is not possible to predict in advance how well a specific individual will respond.  However, it is important for the doctor to determine for sure that a person is truly allergic to a specific allergen and that the allergy is responsible for the symptoms BEFORE starting allergy shots.  If the allergy is not causing the symptoms, allergy shots for that allergy will not help at all.

Note: The content of this blog is for informational purposes only and is not meant as specific medical advice for a specific person.   If you have a medical problem, please contact your doctor.

Allergy Shots Part 3: How Are They Administered And What Are The Side Effects?

June 9, 2010

There are two phases to allergy shots, the build up desensitization phase and the maintenance phase.  Patients are initially started on very low doses of the allergen, and during the build up phase the doses are increased to higher and higher levels until the maintenance dose is reached.   It usually takes about 24 visits to get to the maintenance dose level and these visits are usually weekly or twice a week.  Once the maintenance dose level is reached, the visits are spaced to every 2 to 4 weeks. 

Since allergy shots actually contain the substance that you are allergic to, the main potential side effect is an allergic reaction to the shots themselves.  Because of this possibility, all people on allergy shots, must wait in the doctor’s office for 30 minutes after the shot is given so they can be monitored for the possibility of a reaction.  It is not unusual to have a little itchiness or slight swelling at the site of the shot.  The type of reaction that is concerning and needs to be treated immediately, is a more generalized allergic reaction to the shot, including anaphylaxis.  There have been rare reports of life threatening anaphylaxis resulting from allergy shots.  I always emphasize the importance of waiting a full 30 minutes after receiving a shot since that is the time frame within which the vast majority of reactions will start to occur.  

I prescribe an Epi Pen for all of my patients on allergy shots and ask them to carry it with them the day of their shot.  An Epi Pen is a self-administered shot of epinephrine or adrenaline that is carried routinely by people with life threatening reactions to foods or bee stings.  I think it is a good idea for people on allergy shots to have this with them the day of their shots as an extra level of caution.  Fortunately, I have never had a patient on allergy shots who has had to use an Epi Pen for that purpose.

Patients will sometimes ask me if it is OK for them to administer shots to themselves at home.   The answer to that is simple: NO.  It is never appropriate for allergy shots to be administered outside of a physician’s office or health care facility that is prepared to treat anaphylaxis. 

Note: The content of this blog is for informational purposes only and is not meant as specific medical advice for a specific person.   If you have a medical problem, please contact your doctor.

Allergy Shots Part 2: What Types Of Allergies Have They Been Proven To Effectively Treat?

May 26, 2010

There have been many studies evaluating the effectiveness of allergen immunotherapy or allergy shots.   The most rigorous scientific studies are those that are placebo-controlled and double-blinded.  A placebo-controlled allergy shot study is a study where some patients receive actual allergy shots and some receive injections of saline placebo.  A double-blinded, placebo-controlled allergy shot study is a study that is placebo-controlled and neither the patient nor the physician knows who is getting the allergy shot and who is getting the saline placebo.

Double-blind, placebo-controlled clinical studies have proven that allergy shots improve the quality of life, reduce symptoms and reduce the need for medications in children and adults with the following allergic conditions:

1. Nasal and ocular allergies (Allergic Rhinitis and Allergic Conjunctivitis)

2. Allergy-related asthma

3. Bee sting allergy:  All people who have experienced life threatening reactions to bee stings should be on allergy shots to help prevent these reactions in the future.

Allergy shots have been proven to work for grass pollen allergy, tree pollen allergy, weed pollen allergy,  mold spore allergy, allergy to animals such as cats and dogs, cockroach allergy and dust mite allergy.

Other benefits of allergy shots:

1. About 1/3 of patients with allergic rhinitis (nasal allergies) eventually develop asthma.  Allergy shots can decrease the risk of developing asthma for someone who only has nasal allergies.

2. Someone with an allergy to one allergen, such as dust mite, is at an increased risk of developing an allergy to another allergen, such as tree pollen.     Allergy shots for one allergen can prevent a person from becoming allergic to other potential allergens.

3. Allergy shots can be effective for atopic dermatitis or eczema that is associated with allergy to aeroallergens such as dust mites or pollens. 

4. Some studies have shown that allergy shots might help with the oral allergy syndrome.  (see Tree Pollen Allergy and Foods: The Oral Allergy Syndrome; 4/9/10)

Allergy shots are NOT effective for food allergy and should not be used for hives or angioedema.

Note: The content of this blog is for informational purposes only and is not meant as specific medical advice for a specific person.   If you have a medical problem, please contact your doctor.

Allergy Shots Part 1: What Are They? How Do They Work?

May 25, 2010

Allergy shots, or allergen immunotherapy, is the only FDA approved treatment available to make someone less allergic to a specific allergen.  All other FDA approved therapies for allergies are directed at controlling symptoms.  Allergen immunotherapy is directed at changing the immune response.  Allergen immunotherapy administered with shots is the only FDA approved method in the United States.   There is a lot of ongoing research on administering allergen immunotherapy through droplets under the tongue (sublingual immunotherapy).  This form of immunotherapy is used in Europe.

The purpose of the immune system in general is to protect the body against microorganisms (germs) and act as scavengers within the body to remove defective, dying or abnormal cells.  The allergic arm of the immune system directs itself against otherwise harmless substances such as dust mite or tree pollen with an allergic immune response mainly mediated by the allergen antibody called IgE.    When an allergen and a specific IgE against that allergen is present in an allergic individual, the IgE binds to cells in the immune system causing the immediate release of allergic mediators such as histamine and leukotrienes.  This causes immediate symptoms and initiates a larger and more progressive allergic immune response.  Allergy shots work by changing the immune response away from an allergic immune response. 

There are many complex changes that occur within the immune system with successful allergen immunotherapy.  It is important to note that the changes are very specific and do not affect other aspects of the immune system.  The various changes are as follows:

1. Shifts the immune response toward a non allergic response to the allergen. 

2. Generates specific regulatory immune cells that induce immune tolerance, or a decrease in the immune response, toward the allergen.

3. Induces the production of non allergen antibody called IgG toward the allergen.  These antibodies can block the allergen antibody (IgE) from releasing mediators such as histamine, that are responsible for allergic symptoms. 

4. Blocks the immediate and late phase allergic response.

5. Decreases the recruitment of inflammatory cells that contain mediators to the nose, eyes and lungs. 

6. Decreases the rise in allergen antibody that occurs in allergic individuals during the allergy season. 

Many people think of allergen immunotherapy as a more natural approach to the treatment of allergies since it utilizes the allergens themselves to induce immune changes.  That might be true, but it is important to point out that allergen immunotherapy is NOT a homeopathic approach to allergies.  Homeopathy is based upon treatment using minute quantities of substances.  Allergen immunotherapy starts with minute quantities of allergen, but doses are gradually increased and it only really works when high doses called maintenance doses are administered. 

Stay tuned for more information on allergen immunotherapy. 

Note: The content of this blog is for informational purposes only and is not meant as specific medical advice for a specific person.   If you have a medical problem, please contact your doctor.