Association of Acid-Suppressive Medication and Antimicrobial Use in Infancy with Food Allergy and Anaphylaxis.

The incidence of food allergies and other allergic diseases is rising. Emerging evidence links both antimicrobials and acid-suppressive therapy with gut dysbiosis, which is implicated in allergy development. We investigated the relationship between the use of acid-suppressive medications or antimicrobials in infancy and the risk of developing childhood allergic diseases. The US network in the TriNetX platform was used to identify patients prescribed proton pump inhibitors (PPIs), histamine-2 receptor antagonists (HRAs), antimicrobials ≥1, or antimicrobials ≥3 times during their first year of life from October 2015 to January 2022. ICD-10 diagnoses were used to assess two-year outcomes of anaphylaxis, food allergy, and atopic dermatitis. A sub-analysis in gastroesophageal reflux (GERD) patients was also performed. Risks of anaphylaxis and food allergy increased with the prescription of PPIs (risk ratio [95% CI], 2.49 [1.40-4.41], 5.33 [4.97-5.71]), HRAs (4.48 [3.43-5.86], 4.21 [4.01-4.41]), and antimicrobials ≥1 (2.41 [2.13-2.72], 1.90 [1.86-1.94]), or ≥3 times (3.69 [3.12-4.37], 2.79 [2.70-2.88]). Risk of atopic dermatitis was increased in both HRA (1.41 [1.35-1.48]) and antimicrobial groups (2.25 [2.22-2.28], 3.35 [3.29-3.41]), but not in the PPI group. In the GERD sub-analysis, anaphylaxis risk was not significantly different, food allergy risk was increased in both PPI (2.30 [2.08-2.53]) and HRA groups (1.77 [1.63-1.92]), and atopic dermatitis decreased in the PPI group (0.76 [0.67-0.85]) but slightly increased in the HRA group (1.11 [1.03-1.20]). Exposure to acid-suppressive or antimicrobial medications during infancy was associated with increased risk of food allergy and anaphylaxis in early childhood. In infants diagnosed with GERD, exposure to acid-suppressive medications was still associated with increased food allergy risk.