In Spain, peanut allergy is increasingly prevalent. Successful protocols for the induction of oral tolerance (IOT) with several foods have been reported. We aimed to induce clinical tolerance to peanut in a child with severe peanut allergy (age 4 years, facial urticaria and lip angioedema upon licking a peanut; peanut skin prick test, 13 10 mm; specific immunoglobulin (Ig) E > 100 kUA/L). At age 6, the threshold oral challenge dose was 62.5 mg. Several peanut solutions were prepared and sequentially administered at the patient’s home. Over 138 days, the dose was increased from 0.625 to 5500 mg. There were 43 mild-to-moderate reactions (28% of the doses administered). Pre-IOT and post-IOT peanut IgE and IgG4 values were 265 vs 487 kUA/L, and 6.11 vs 14.8 mg/L. This is the first report of successful IOT to peanut in Spain. This home-based regimen is safe under permanent and close medical supervision by an allergist.

Key words: Induction of oral tolerance. Peanut allergy. Desensitization. Home-based.