Most such patients tolerated escalating doses of store-bought peanut butter. 

Peanut allergy affects about 2% of people in the USA. Some patients have allergic reactions to tiny amounts of peanut protein (less than 100 mcg), but others have higher thresholds and can tolerate one half of a peanut (100 mg of peanut protein) or more. Researchers examined a peanut-desensitisation protocol using store-bought peanut butter in these patients with higher thresholds.

Seventy-three children (age range, 4 to 14 years) who were allergic to peanut butter but could tolerate at least 143 mg of peanut protein were randomised to a peanut butter protocol or peanut avoidance. Patients started with about one-eighth of a teaspoon of peanut butter daily (137 mg of peanut protein) and increased the dose every eight weeks for 18 months until they reached a daily dose of one tablespoon (3396 mg of protein). Thirty-two of 38 patients who were randomised to peanut butter completed the protocol; all completers (versus 10% of the avoidance group) could tolerate a 9043 mg peanut protein challenge. Thirty patients who completed the peanut butter protocol then avoided peanuts for eight weeks; 26 of those patients then tolerated another high-dose peanut challenge, which indicates ‘sustained unresponsiveness.’

Comment: Current therapy for peanut allergy includes avoidance, the US Food and Drug Administration-approved peanut powder Palforzia (US$10,600 annually) and the monoclonal antibody omalizumab (Xolair; US$30,000 to US$60,000 annually). For patients with higher-threshold peanut allergies, using peanut butter to encourage tolerance is much cheaper and seems to be very effective.

David J. Amrol, MD, Associate Professor of Clinical Internal Medicine, Director of the Division of Allergy and Immunology, University of South Carolina School of Medicine, Columbia, USA.

Sicherer SH, et al. Peanut oral immunotherapy in children with high-threshold peanut allergy. NEJM Evid 2025 Feb 10; e-pub (https://doi.org/10.1056/EVIDoa 2400306).

This summary is taken from the following Journal Watch titles: General Medicine, Ambulatory Medicine, Pediatrics and Adolescent Medicine.