Age and indications to SLIT.

Clinical efficacy of sublingual immunotherapy (SLIT) has been investigated during the last 20 years and results of several meta-analyses are available, showing clinical efficacy of SLIT in children both in allergic asthma and in rhinitis, but strict recommendations are not possible under current evidence. Minimum age for starting SLIT is not clearly defined but several position paper and guidelines indicate a lower limit of 5 years of age. Guidelines on allergic rhinitis suggests SLIT in patients not well controlled with drugs or those who refuse to use drugs. Additional effects are prevention of new sensitizations (evidence IIa) and prevention of asthma in patients with allergic rhinitis (evidence I b). Studies on efficacy of SLIT in asthmatic children are discordant, but the different relevance of allergic and non allergic triggers of symptoms could explain the discordant results obtained in studies on SLIT and asthma, particularly when pooling short and long term studies. Data on efficacy and safety of SLIT are accruing for atopic dermatitis, food allergy and latex allergy, but at the current state of knowledge, SLIT remains an approach reserved to research, and no recommendations can be established. Some studies demonstrate that SLIT is safe in children below 5 years of age, with a lower limit of 3 years.