Adverse reaction to sublingual Parietaria vaccine following an ultra-rush induction

In the treatment of respiratory allergies Sublingual Immunotherapy (SLIT) represents a valid alternative to Subcutaneous Immunotherapy (SCIT) for its better safety profile. We describe a case of acute severe asthma following the first maintenance dose of SLIT in a boy allergic to Parietaria pollen. At the initiation of therapy, the patient was in healthy condition and his asthma appeared to be under control. An ultra-rush induction had given no reaction. Despite the good safety profile of SLIT, clinicians should be aware of the risk of adverse effects when prescribing SLIT for respiratory allergies.