A clinical trial on Sublingual Immunotherapy (SLIT) for food allergies is being conducted at the University of Missouri-Columbia.
SLIT is a method of allergy treatment unlike traditional antihistamines, topical nasal corticosteroids, and injections. A tablet of the allergen is placed under the patient’s tongue and is absorbed through the mucous by the dendritic cells, which then move to the lymph nodes and interact with lymphocytes, inhibiting the immune reaction.
The precise mechanism for the action of SLIT remains unclear, and the therapy is not recommended for patients with active auto-immune or malignant conditions.
A previous meta-analysis of 21 clinical trials with common allergies caused by environmental particles such as pollen grain, and house-dust mites, showed the effectiveness of SLIT in reducing symptoms of sneezing, itching, nasal discharge, and blockage.
In more recent large trials of 1600 patients, 82% of patients reported feeling better compared to 55% of placebo patients.
Some of the adverse effects of SLIT that were observed included local irritation of the mouth and tongue areas (47-52%), itching with a 50% chance of disappearance within 8 days (50%), palatal swelling, and throat irritation.
The efficacy of SLIT in children remains to be researched, as a few studies have reported negative effects. As well, no firm recommendations on dosage and duration of SLIT have yet been provided.
The current study focuses on SLIT as a possible therapy for food allergies.
ClinicalTrials.gov. “Sublingual Immunotherapy for Food Allergy.” Available from: http://clinicaltrials.gov/ct2/show/NCT00736281?term=allergy&rank=9. Last accessed: Oct. 4, 2013.
Frew, A.J. “Sublingual immunotherapy.” New England Journal of Medicine. 358: 2259-2264. May 22, 2008. Available from: 10.1056/NEJMct0708337
Wilson, D.R., Torres Lima, M., & Durham, S.R. “Sublingual immunotherapy for allergic rhinitis: systematic review and meta-analysis.” European Journal of Allergy and Clinical Immunology. 60(1): 4-12.
Written by Julia Yusupova