ABSTRACT
Sublingual allergen-specific immunotherapy (SLIT) is a standard modality of treatment for respiratory allergy. Its efficacy and safety are well demonstrated in clinical trials and postmarketing surveys. The large majority of adverse events with SLIT are local (upper or lower digestive tract), transient, and do not require discontinuation. Systemic events (urticarial, rhinitis, asthma) are rare and can be easily treated by standard therapy, whereas anaphylaxis is exceptional and only a few cases have been reported in more than 30 years of use. The safety of SLIT is not influenced by the use of multiple allergen extracts given separately, and it can be prescribed also in young children (usually older than 4 years of age). It is recommended that only products approved by the regulatory agencies are used, that patients must be instructed in detail, and that the first dose is given under medical supervision. The oral and sublingual administration of allergens is a promising perspective for food allergy, but in this case, the safety aspects remain critical, and this approach is not recommended for standard care.
