Adherence to allergen-specific immunotherapy is better for SLIT than SCIT

Allergen-specific immunotherapy can modify the natural history of the allergic diseases, reducing the development of asthma and new sensitizations after 3-4 years of treatment. In order for immunoterapy to work however, adherence to the therapy is mandatory.

Rate of adherence to subcutaneous immunotherapy (SCIT) is low, at less than 70%. The possible explanations for that fact include the following factors:

- inconvenience
- lack of perceived efficacy
- costs and loss of working hours

In comparison, local nasal immunotherapy has a even lower adherence rate (27%), due to the local nasal side effects.

For sublingual immunotherapy (SLIT), the rates of compliance are greater than 75%.

The reasons for discontinuation of SLIT are:

- costs
- inconvenience
- feeling of inefficacy
- side effects

In real life, costs and patient education are crucial issues in adherence to this SCIT and SLIT. Reduction of costs and more efforts in education of patients may improve the adherence to immunotherapy.

References:
Evidence of adherence to allergen-specific immunotherapy. Senna G, Ridolo E, Calderon M, Lombardi C, Canonica GW, Passalacqua G. Curr Opin Allergy Clin Immunol. 2009 Dec;9(6):544-8.

SCIT ("allergy shots") is at least as potent as pharmacotherapy in controlling the symptoms of allergic rhintis as early as the first season of therapy. JACI, 2011.
Image source: OpenClipArt.org, public domain.