Immunotherapy is a treatment process aimed at permanently reducing the effects of allergies. Many people develop allergies during childhood and often grow out of their allergies by the time they reach adulthood. Some of us, however, aren't that lucky, with persisting symptoms that often intensify with time. Our bodies are reacting, or over-reacting, to generally harmless substances and immunotherapy provides a way of convincing the immune system that the allergen isn't a threat.
Immunotherapy is particularly useful if allergies are caused by substances that are not easily avoidable. Others that will benefit from the treatment are people who are no longer responding to medication or who experience unpleasant side-effects to the medication.
After too many years of asthma attacks, sneezing, itchy eyes and other accompanying hay fever symptoms I began looking around for alternative treatments. I read about immunotherapy in Reversing Asthma by Richard N. Firshein, undertook further research (summarised in this writeup), and subsequently made a decision to undertake this course of treatment.
How it works
The exact mechanisms behind the effects of immunotherapy are still under investigation. Antibodies are molecules that essentially hunt down and trigger the destruction of antigens. B cells encounter the antigen and generate plasma cells which then mass produce antibodies with high specificity and affinity for that particular antigen. Immunoglobulin E (IgE) is the antibody involved during allergic reactions and is responsible for the release of histamine (among other chemicals) which results in inflammation and smooth muscle contraction to the dread of every asthmatic.
An antigen's route of entry into the body determines what type of antibody will be produced against it. For example, if pollen enters through the mucous membranes, such as the nose, IgE is produced, but if the pollen is injected subcutaneously then Immunoglobulin G (IgG) is produced, essentially blocking the histamine release. Individuals suffering from severe allergies have higher than normal levels of serum IgE levels and therefore an allergic reaction is more likely to occur. Immunotherapy is thought to decrease the levels of IgE, reducing the likelihood of an allergic response.
Allergies it combats
Immunotherapy has proven to be very effective against inhaled allergens such as grass, pollen, house dust mites and animal dander. It is ineffective against food allergies because IgE mediated responses to food are only a small part of the overall immune response. If food allergies are suspected to be the problem then an elimination diet may be more beneficial.
Procedure
Immunotherapy is commenced pre-seasonally so that maintenance injections can be reached before the beginning of the pollen season. Initially, a very weak dose of purified allergen is injected subcutaneously on a weekly basis for 3-4 months, although it can be twice a week. If you hate injections, as I do, this one is really quite painless because it's only going just under the skin instead of into the muscle. Each week the dose is slightly more concentrated with the highest dose reached after the 4 months. Maintenance injections are then given monthly for 2-3 years, sometimes for up to 5 years. It's important that treatment is received regularly in order to receive the maximum benefit.
Benefits
Immediate improvement is not evident, but 6-12 months later considerable improvement may be recognised. Studies have shown that people who have undergone immunotherapy experience reduced severity of symptoms and need for medication. It's likely that the introduction of immunotherapy treatment shortly after the diagnosis of an allergy in children could prevent that particular allergy from becoming severe, and may prevent the onset of additional allergies.
Side Effects
A pre-dosing of an antihistamine helps to minimise effects and people are required to remain in the clinic under the medical supervision of their allergy specialist for up to forty-five minutes after each injection. Generally everyone will experience redness and itching at the site of the injection. Exercising after treatment is not recommended and it's not safe for those taking Beta-blockers which are heart and blood pressure drugs. Immunotherapy is not readily given to pregnant women and treatment may be stopped in the event of pregnancy. If the expectant mother experiences side effects, the baby's oxygen supply might be reduced. However, treatment may be allowed to continue if the expectant mother is not experiencing serious side effects.
The doctor will reduce the dosage in the event a person feels sick, develops severe itching (eyes, nose and throat) or a rash, or experiences increased wheezing. Although extremely rare, a person may suffer anaphylactic shock which can be fatal. In this instance the side effects include a sudden appearance of hives, watery nasal discharge, sneezing, swelling of the lips, tongue or mouth, wheezing or breathing difficulties, nausea, dizziness, an increased pulse along with a drop in blood pressure.
Where to now?
If you have reached a point, as I did, where allergies are disruptive to your life both physically and mentally, then consider immunotherapy. Check out the links below and ask your doctor for a referral to an allergy specialist. While it is not a quick fix, the benefits are definitely rewarding.
References
http://rex.nci.nih.gov/PATIENTS/INFO_TEACHER/bookshelf/NIH_immune/html/imm07.html
http://www.asthma-drsprecace.com/immuno.html
http://www.aaaai.org/patients/publicedmat/tips/whatareallergyshots.stm
http://www.allergycapital.com.au/Pages/immthsafety.html
Information from my allergy specialist