Timing of cow's milk oral immunotherapy and adverse reactions in children: A 15-year experience.

BACKGROUND

Cow's milk allergy (CMA) is one of the most common food allergies in children and may persist into later childhood. Oral immunotherapy (OIT) is an effective treatment option; however, the optimal timing of initiation and the mechanisms underlying age-related differences in safety remain uncertain.

OBJECTIVE

To evaluate the safety and efficacy of cow's milk OIT initiated at different ages and to explore the relationship between age, baseline immunologic markers, and adverse reactions in a real-world pediatric cohort.

METHODS

We retrospectively analyzed 145 children with IgE-mediated CMA who completed OIT between 2009 and 2024. Patients were grouped by age at OIT initiation (<24 months, 24-48 months, and >48 months). Baseline clinical and laboratory characteristics and OIT-related adverse events (AEs) were compared. Multivariable logistic regression analyses were performed adjusting for relevant clinical covariates to assess the independent effects of age and cow's milk-specific IgE (CM-spIgE) on AEs.

RESULTS

Older children (>48 months) had significantly higher baseline total IgE and CM-spIgE levels and more frequent pre-OIT anaphylaxis and respiratory symptoms. The use of omalizumab and epinephrine was more common in older patients. In multivariable analyses, age and CM-spIgE were each associated with adverse reactions. Early OIT (<24 months) was associated with fewer severe reactions and no anaphylaxis during the maintenance phase.

CONCLUSION

Earlier initiation of cow's milk OIT seems to be associated with a more favorable safety profile, highly correlated with the baseline immunologic profile. These findings support personalized decision-making that includes age and immunologic markers when determining OIT timing.