Allergy vaccination is a treatment option in long-term and severe allergy where the patient benefits from normal drug treatment have proved unsatisfactory. The treatment is also called hyposensitisation or specific immunotherapy, and should not be confused with cortisone injections used in the treatment of allergy.
Allergy vaccination is based on the giving of small doses containing extracts of the allergen to which the individual reacts, which are injected under the skin. The initial doses should be low so as not to trigger an allergic reaction. The doses are gradually and carefully increased up to the highest tolerated dose. This maintenance dose is normally given every 6-8 weeks for a period of 3-5 years. In this way tolerance can be built up to the allergens used in the treatment.
For which conditions can the treatment be used?
Allergy vaccination can be used to treat most forms of pollen allergy (birch, hazel and grass). Allergy vaccination is also used to reduce the risk of life-threatening reactions in patients with serious bee or wasp allergy. In individual cases individuals are vaccinated against animal and mite allergies. Studies have shown that allergy vaccination can protect against subsequent development of asthma or provide better control of an allergic asthma. Allergy vaccination should not however be used in patients with severe asthma.
Who can receive the treatment?
Before allergy vaccination is considered, normal allergy treatment with antihistamines and local agents for eye and nose symptoms should be thoroughly explored. If the symptoms persist in spite of this, allergy vaccination may be a good alternative.
Allergy vaccination is not recommended for children below the age of 5 years, or for patients with uncontrolled asthma, serious cardiovascular disease or cancer. The treatment should not be commenced during pregnancy. Allergy vaccination may only be commenced following thorough investigation, allergy testing and lung-function tests with a specialist. Referral to a specialist may be done by a general practitioner.
Where is the treatment performed?
Allergy vaccination should only be performed by a specialist in hospital medicine, an Ear, Nose and Throat specialist and paediatricians with specialist allergological expertise. This is because the treatment may involve risk of side effects, particularly during the start phase.
Costs for the actual vaccine are refundable under the National Insurance Service’s blue prescription regulations. As of 1st July 2003, a special refund payment has also been introduced for allergy vaccination.
Risk of side effects
Allergy vaccination is associated with a certain risk of side effects. These may range from mild symptoms such as a stuffy nose, itchy eyes and throat, to serious or life-threatening symptoms in the form of breathing difficulty or allergic shock. This applies particularly during the start phase and immediately following injection. The treatment should therefore take place at special units where equipment is always on-hand for the management of any serious reactions. During the first day after an injection patients may also experience local reactions such as swelling of the skin.
What are the effects of the treatment?
There is documentation that allergy vaccination is an effective form of treatment which can reduce allergy symptoms and, thereby use of other medicinal products, significantly. Following completion of treatment the effects may persist for at least 6 years. Some individuals will not however experience significant improvement, and it is not currently possible to select in advance who will benefit from the treatment.
Allergy vaccination is in itself a relatively time-consuming and expensive form of treatment. The risk of side effects, coupled with the fact that not all individuals will experience improvement following the treatment, must be considered carefully before selecting this form of treatment.
Development of new and improved forms of immunotherapy will hopefully provide safer treatment and better results in the future (see below).
Facts:
Studies show that 26.8% of the population in Norway suffer from asthma or allergy. There are close to 900,000 individuals with pollen allergy in Norway, 300,000 of whom are severely affected. In Norway approximately 1,400 patients have been treated with allergy vaccination since 1999. This is far lower than in the other Scandinavian countries.
The Norwegian Asthma and Allergy Association believes
Allergy vaccination should exist as an accessible and real treatment alternative for patients with severe hay fever who do not benefit from usual drug therapy. Increased access to a safe treatment should occur through improved information about the treatment forms available and where the treatment can be performed. NAAF feels that several special units should be established which can perform allergy vaccination in accordance with applicable regulations. Research efforts should be focused on finding simpler and safer forms of immunotherapy.
Future forms of treatment in allergy:
Allergy vaccination in tablet form to treat grass pollen allergy is under trial in Norway. By providing the allergen in tablet form a greater proportion of the treatment could be performed at home, thereby avoiding the need for frequent visits to the doctor. It is still too early to say to what extent the tablets can provide long-term or only temporary immunity against grass pollen.
Other forms of immunotherapy have also been developed studying the viability of producing gene-modified variants of the allergens used in allergy vaccination.
The allergy-triggering antibodies are called IgE. A completely new treatment form involving injections of anti-IgE has also been trialled. Studies have shown good results for quite special indications. Anti-IgE is currently available in Norway.