The Asthma-Antibiotics Link

Why should you care about this if asthma does not run in your family? For the last quarter century, asthma has been increasing rapidly in the industrialized world and has become one of the most important chronic illnesses of children. It’s unlikely that this recent increase has come from changes in children’s genes. Instead, changes in diet, activity, and environmental exposures could all contribute. A number of studies have suggested a link between antibiotic use and asthma.

But is it that children’s tendency toward asthma causes more respiratory infections and the need for more antibiotics? Or that greater antibiotic use can trigger asthma? To answer this question, the Study of Asthma, Genes, and the Environment has been following 13,116 children born in 1995. The results of the study were published in the June 2007 Chest.

It looks like the antibiotic use can trigger asthma – probably by altering our internal environments by killing beneficial bacteria in the gut that are needed for optimum immune development. In this study, the children who received antibiotics in the first year of life were more likely to have developed asthma by age 7– whether or not the antibiotics were for respiratory infections. Those who received more than four courses of antibiotics before the first birthday were about 1.5 times more likely to end up with asthma than their peers. The effect was strongest for broad spectrum antibiotics. The connection was clearest for children without a strong family history of asthma.

Antibiotics are important, life-saving tools. Nevertheless, it is wise to avoid over-using them. They should only be used where there is a considerable benefit to the child. And when they are used, it is wise to select the narrowest-spectrum antibiotic appropriate, in order to preserve beneficial bacteria when possible. I am also a fan of giving children probiotics and/or prebiotics whenever antibiotics are given, to help replenish the healthy, helpful bacteria in their guts. This could help reduce side effects (such as diarrhea) and help to prevent later allergic diseases such as eczema or asthma.

Kozyrskyj, A.L., Ernst, P., and Becker, A.B. “Increased Risk of Childhood Asthma from Antibiotic Use in Early Life.” Chest. 2007, 131, pp. 1753-1759.