Is Acetaminophen a Culprit in Asthma?

During the past decade, epidemiologic studies have shown a positive association between acetaminophen use and asthma prevalence and severity in adults and children. In a special article in Pediatrics, a pediatric pulmonologist reviews these data.

Results from a large international study showed a significant threefold higher risk for current asthma in 6- and 7-year-olds who took acetaminophen at least once per month. The authors of this study assert that if acetaminophen does indeed exacerbate asthma, it would account for about 40% of the population-attributable risk for severe asthma symptoms. But what if children with asthma are just more likely to take acetaminophen, or have viral infections that lead to both asthma symptoms and acetaminophen use? In the Boston University Fever Study, researchers randomized febrile children (age range, 6 months–12 years) to receive acetaminophen or ibuprofen for fever. In the subset of children with asthma, those who received acetaminophen were twice as likely to have a subsequent outpatient asthma visit as those who received ibuprofen.

Also noted in the review are studies that have shown dose-response associations, the observation that asthma prevalence and acetaminophen sales have increased in tandem during recent decades, and a plausible mechanism of action by which acetaminophen could increase susceptibility to asthma by depleting airway mucosal glutathione.