Allergen immunotherapy for allergy (desensitisation)
A daily under-the-tongue tablet that builds tolerance to an allergen, the only treatment that can change the course of allergy.
Sublingual immunotherapy (SLIT) treats allergy by gradually exposing your immune system to small, controlled amounts of the allergen you react to, so your body builds tolerance over time. It is taken as a tablet placed under the tongue once a day, at home. Unlike sprays and antihistamines, which control symptoms, immunotherapy is the only treatment that can change the underlying course of the allergy.
Is it right for me?
Allergy testing first confirms what you are allergic to and whether immunotherapy is suitable. It is most often used for house dust mite, or grass and tree pollen allergy, that stays troublesome despite standard treatment.
How it is taken
- The first tablet is taken in clinic so any reaction can be observed; take an antihistamine an hour or two beforehand
- Place the tablet under the tongue with dry fingers; it dissolves in seconds. Avoid swallowing for a minute and food or drink for five minutes
- You then take it every morning at home, usually for about three years
- Reviews follow at about one month, then three and six months
Safety and side effects
Immunotherapy is generally safe. The commonest side effects are mild and local: itching or swelling under the tongue, and sometimes mild tummy upset, which usually settle and can be eased with a daily antihistamine. Severe reactions are rare, and anaphylaxis is extremely rare, which is why the first dose is supervised.
Alternatives
You can continue standard treatment (saline rinse, antihistamine and a steroid nasal spray), which controls symptoms but does not change the allergy. Immunotherapy can also be given as injections by a doctor, rather than as self-administered tablets.
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This guide is general information and not a substitute for individual medical advice. Contact the practice if you have questions about your own care.