COPD is an acronym for chronic obstructive pulmonary disease, it includes emphysema and bronchitis. Research appearing in the May, 2005 issue of the American Journal of Respiratory and Critical Care Medicine contains research that connects acetaminophen use with asthma and COPD. “Oxidative stress may increase the risk of asthma, contribute to asthma progression, and decrease lung function,” write Tricia M. McKeever, MD, from the University of Nottingham, England, and colleagues. “Previous research suggests that use of acetaminophen, which is hypothesized to reduce antioxidant capacity in the lung, is associated with an increased risk of asthma.”

Increased use of acetaminophen (sold under the brand name “Tylenol”) was associated with COPD and asthma—the higher the use of the drug, the higher the incidence of these two lung diseases. Use of acetaminophen was also associated with a decrease of lung function in general. Daily users of the drug had lower forced expiratory volume (a measure of lung function) when compared to people who never took the drug.