What is Desensitisation?
Allergen immunotherapy, also known as desensitisation, is a medical treatment aimed at changing the body’s immune system to make it less reactive to a specific substance. Ideally the body becomes tolerant of the substance and the allergic symptoms stop (or are substantially reduced). Desensitisation involves administration of escalating doses of allergen, either via injection (subcutaneous immunotherapy) or via the mouth (sublingual and oral immunotherapy). Immunotherapy is particularly useful for airborne allergens (dust mites, pollens, grasses, animal fur). It is also used to treat insect venom allergies in specialist centres.
- Allergy Immunotherapy is the only available pharmacotherapy that can alter the natural history of respiratory allergic disease.
- It provides a well established and effective treatment in patients with moderate to severe allergic rhinitis and / or allergic asthma, who haven’t responded sufficiently to symptomatic drug therapy.
- Administered via injection as Subcutaneous Immunotherapy (SCIT) or via drops / tablets as Sublingual Immunotherapy (SLIT).
- SCIT significantly helps about 80% of patients with hay fever and about 60% of people with HDM (house dust mite) allergy. On average people have a 2/3 symptom reduction meaning much less symptoms and less medication use. For some people they experience a complete cure.
- The clinical efficacy is similar for both methods, and can provide long lasting improvements in symptoms and quality of life.
- SCIT involves a series of injections over 3-5 years. Each injection must be performed under medical supervision. There is a risk of systemic allergic reactions (< 1% of injections). Post-SCIT severe reactions including anaphylaxis range from 0.1 to 0.2% of injections and from 2 to 5% of patients.
- SLIT has a number of advantages and has become increasingly popular over recent years:
- Drops / tablets (vs injection)
- Self administration at home (vs medical administration in a clinic)
- Lower risk of systemic reactions (<0.1%)
Due to its better safety profile, only SLIT is prescribed at East Ringwood Clinic. SCIT (on the few occasions it is required) is initiated in collaboration with a specialist.