excerpt jpost.com

Sublingual immunotherapy - in which the immune system is primed by
exposure to allergens in liquid concentrate form dripped and held for
a few minutes under the tongue - is a very promising and safe new way
of treating asthma, allergic rhinitis (runny nose) and other
allergy-related conditions in all age groups, according to researchers
at the Rabin Medical Center-Beilinson Campus.

Writing in Harefuah, the Hebrew-language journal of the Israel Medical
Association, Prof. Monda Iancovici Kidon and Prof. David Nelken note
that conventional immunotherapy consists of injecting agents into the
skin in increasing amounts and on a controlled basis; this causes the
body's immune system gradually to produce antibodies and minimize the
allergic response. The down side is that the injected allergens may
cause side effects such as redness, swelling and pain at the injection
site (which is especially difficult for children), nasal drip,
constriction of the bronchi and even anaphylactic shock.

The authors looked at numerous controlled studies of sublingual
treatment published since 1985 and concluded that it has great
potential in replacing injections, even though larger clinical studies
are needed. The mechanism for sublingual therapy in which the allergen
passes through the digestive system is not yet well understood, but it
works. Published studies showed that sublingual immunotherapy was
nearly as effective in minimizing allergies as injections.