Information for Our Community

Whether you are part of our community or are interested in joining us, we welcome you to Washington University School of Medicine.


Visit the News Hub

Acetaminophen does not worsen children’s asthma symptoms

Over-the-counter pain reliever and fever reducer can be given safely to kids with mild asthma

by Julia Evangelou StraitAugust 17, 2016


Pediatricians often recommend against giving the pain reliever and fever reducer acetaminophen to children with asthma because some studies have suggested the medication can worsen asthma symptoms. But a new study in young children with asthma comparing acetaminophen to ibuprofen – another pain and fever reliever – shows no difference in the severity of asthma symptoms between the two medications.

The study, led by Boston Children’s Hospital and Harvard Medical School, is published Aug. 17 in the New England Journal of Medicine. The study involved 300 children treated at 18 U.S. study sites, including Washington University School of Medicine in St. Louis and St. Louis Children’s Hospital.

“Parents tend to give acetaminophen to children who have fevers or other symptoms related to viral infections, and those viral infections are known to be common triggers of asthma episodes,” said co-author Leonard B. Bacharier, MD, a pediatric asthma specialist at Washington University School of Medicine in St. Louis. “So from past studies, we couldn’t tell if it was the acetaminophen or the virus that was causing the increased likelihood of the asthma episodes.”

Acetaminophen, also sold under the brand name Tylenol, and ibuprofen, sold under brand names Advil and Motrin, are over-the-counter medications that parents give children to relieve pain and reduce fevers.

In the current study, children from ages 1 to 5 with asthma were randomly assigned to receive either acetaminophen or ibuprofen for pain relief or fever reduction as needed. Participants, caregivers and treating physicians did not know which drug each child received since the two liquid medications were made to look and taste identical with identical dose volumes.

All children in the study had a diagnosis of mild, persistent asthma, meaning they require daily medications to control their asthma and experience symptoms at least twice per week but not daily.

The researchers found no difference in the number of exacerbations of asthma symptoms between the two groups, no difference in the need for rescue therapy, such as the use of rescue inhalers, and no difference in the number of days the children experienced good control of their asthma symptoms. There also was no difference in the number of unscheduled medical visits between groups.

The results of this study can’t be extrapolated to children with severe asthma, but the new data indicate that parents and caregivers can safely give either acetaminophen or ibuprofen to young children with mild asthma without being concerned that the medications will exacerbate asthma symptoms, Bacharier said. 

The research is supported by grants from the National Institutes of Health (NIH) including HL098102, HL098096, HL098075, HL098090, HL098177, HL098098, HL098107, HL098112, HL098103, HL098115, TR001082, TR000439, TR000448, TR000454, K23AI104780, and K24AI106822. The clinical trials network involved in the study, called AsthmaNet, is supported by a cooperative agreement with with the National Heart, Lung, and Blood Institute (NHLBI).

Phipatanakul W et al. Acetaminophen versus ibuprofen in young children with mild persistent asthma. New England Journal of Medicine. Published August 18, 2016.

Washington University School of Medicine‘s 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient-care institutions in the nation, currently ranked sixth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Julia covers medical news in genomics, cancer, cardiology, developmental biology, otolaryngology, biochemistry & molecular biophysics, and gut microbiome research. In 2022, she won a gold award for excellence in the Robert G. Fenley Writing Awards competition. Given by the Association of American Medical Colleges, the award recognized her coverage of long COVID-19. Before joining Washington University in 2010, she was a freelance writer covering science and medicine. She has a research background with stints in labs focused on bioceramics, human motor control and tissue-engineered heart valves. She is a past Missouri Health Journalism Fellow and a current member of the National Association of Science Writers. She holds a bachelor's degree in engineering science from Iowa State University and a master's degree in biomedical engineering from the University of Minnesota.