Infant Study Links Antibiotics and Asthma

Join Our Community of Science Lovers!


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Antibiotics prescribed for infants within six months of birth may be contributing to increased rates of asthma, scientists say. The results of a new study suggest that babies who receive the medications are more than twice as likely to develop asthma than are children who did not take antibiotics. The findings were presented Tuesday at the annual meeting of the European Respiratory Society in Vienna.

Numerous studies have been designed to try and elucidate the relationship between childhood exposures and increased rates of asthma and allergies, often with conflicting results. In the new work, epidemiologist Christine Cole Johnson of the Henry Ford Hospital in Detroit and her colleagues followed 448 children from birth until they were tested by an allergist at the age of six or seven. About half of the subjects had received antibiotics at least once by the time they reached six months of age. The researchers found that these children were 2.5 times more likely to develop asthma than those who did not receive such treatment. "I'm not suggesting children shouldn't receive antibiotics," Johnson cautions. "But I believe we need to be more prudent in prescribing them for children at such an early age. In the past, many of them were prescribed unnecessarily, especially for viral infections like colds and the flu when they would have no effect anyway."

The scientists also reported a link between the medications and the development of allergies to pets, ragweed, grass and dust mites. They found that children who had taken antibiotics were 1.5 times as likely to develop allergies than children not given the drugs. The findings also support results published last year in the Journal of the American Medical Association, which indicated that early exposure to more than one pet lowers a child's risk of allergies. For children given antibiotics who lived with fewer than two pets, the risk of allergies rose slightly to 1.7 times that of kids who had not received antibiotics, whereas their risk of asthma increased to three times that of children who hadn't taken the drugs.

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe