Frequent Use of Antibiotics Linked to Asthma, Allergies in Children

A new study conducted by Rutgers Health researchers and published in the Journal of Infectious Diseases found that multiple antibiotic courses in children were associated with an increased risk of asthma, food allergies, intellectual disabilities, and allergic rhinitis.¹

Antibiotics are a class of medication that can treat infections caused by bacteria. These can include strep throat and urinary tract infections.² However, antibiotics can also have an effect on the human microbiome, including in children.¹ Allergies and neurodevelopmental conditions have been linked to the increased use of antibiotics in this vulnerable group. This study used a cohort- and sibling-matched design to analyze these potential associations between antibiotic exposure before age 2 years and development of asthma, allergies, autoimmune, or neurodevelopmental conditions through age 12.

The researchers used the electronic health record database Clinical Practice Research Datalink GOLD, which is based in the UK. The data collected were from 1987 to 2020. All children in the Mother-Baby Link files were considered for the study. Children were included in the study if they were in the database starting at 3 months of age, had data available through at least 27 months, and had complete prenatal data. Children were excluded from the study if they were diagnosed with 1 of the outcomes prior to 27 months of age. All participants were assessed for their exposure to antibiotics during their first 27 months of life.

The primary outcome of this study was the diagnosis of asthma/allergies, autoimmune, or neurodevelopmental conditions between 27 months and 12 years of age. Maternal comorbidities, concomitant medications, infections during pregnancy or early childhood, socioeconomic status, prenatal and perinatal factors, and health care utilization were all considered confounders.

Of the 1,091,449 children included, 685,665 were exposed to antibiotics between their birth and age 2 years. Children who took antibiotics were more likely to have had infections, second-hand smoke exposure, and clinical visits outside of general practice and were more likely to be female.

Overexposure to antibiotics could lead to children having an increased risk of asthma, allergies, and intellectual disabilities | Image credit: greenapple78 - stock.adobe.com

The risk of asthma and allergic outcomes by 6 and 12 years of age was higher in children who were exposed to antibiotics. The risk differences (RDs) were higher in asthma (3.5%-4.4%) and atopic dermatitis (3.7%-5.1%). Asthma (adjusted HR [AHR], 1.24; 95% CI, 1.22-1.26) and food allergy (AHR, 1.33; 95% CI, 1.03-1.10) were associated with antibiotic exposure in the full cohort before 2 years of age. Older children had lower AHRs for asthma and higher for food allergies.

Children receiving more than 5 courses of antibiotics had an increased risk of both asthma (AHR, 1.52; 95% CI, 1.49-1.55) and food allergies (AHR, 1.53; 95% CI, 1.42-1.64). This association was also found for allergic rhinitis but was less significant (AHR, 1.18; 95% CI, 1.13-1.23).

In contrast, autoimmune disorders had a less than 0.1% difference in RDs by 12 years of age when comparing those who were exposed to antibiotics and those who were not. There was a weak correlation between antibiotic exposure and ADHD in the full cohort (AHR, 1.08; 95% CI, 1.02-1.15). Other neurodevelopmental outcomes were not significant.

There were some limitations to this study. Certain confounders did not have enough data in the database, which could have led to some not being calculated. Only maternal history was taken into account when it came to parental conditions. Conditions that are more often diagnosed at older ages could have been overlooked due to only looking at younger ages. It is possible that patients were prescribed antibiotics without taking them. Effects of antibiotic exposure could have been underestimated in those with certain autoimmune and neurodevelopmental outcomes due to the exclusion of children with visits outside of primary care in the sensitivity analysis. Certain models could have been biased due to the misclassification of outcomes. False-positive findings could be possible due to the many analyses performed.

“Antibiotics are important and sometimes life-saving medicines, but not all infections in young kids need to be treated with antibiotics. Parents should continue to consult with their children’s doctors on the best course of care,” Daniel Horton, MD, MSCE, FISPE, lead author of the study and a professor at Rutgers School of Public Health, said in a news release.³

The researchers concluded that there was an association between antibiotic use and asthma, food allergies, and intellectual disabilities, with no significant association between antibiotics and autoimmune, neurodevelopmental, and psychiatric conditions.

References

1. Beier MA, Setoguchi S, Gerhard T, et al. Early childhood antibiotics and chronic pediatric conditions: a retrospective cohort study. J Infect Dis. Published online April 16, 2025. doi:10.1093/infdis/jiaf191
2. Antibiotics. Cleveland Clinic. Updated May 24, 2023. Accessed April 17, 2025. https://my.clevelandclinic.org/health/treatments/16386-antibiotics
3. Frequent use of antibiotics in infants and young children may increase risk for asthma, allergies and other conditions. News release. Rutgers School of Public Health; April 16, 2025. Accessed April 17, 2025. https://sph.rutgers.edu/news/frequent-use-antibiotics-infants-and-young-children-may-increase-risk-asthma-allergies-and