Acetaminophen may have link to adult asthma

The common over-the-counter pain drug, acetaminophen, has already been linked to liver damage, hearing loss and deafness, high blood pressure, and other dangerous side effects.

A report  published in the April 2004 issue of the American Thoracic Society’s, American Journal of Respiratory and Critical Care Medicine, says the drug may also be a key cause for the recent increase in cases of adult-onset asthma.

Dr. R. Graham Barr, of the Columbia Presbyterian Medical Center in New York, and colleagues reviewed data from more than 120,000 women who were part of the Nurses Health Study. During a six-year follow-up, 346 women were diagnosed with asthma. As acetaminophen use increased, so did the risk of asthma. Compared with nonusers, women who took the drug more than 14 days per month were 63% more likely to develop asthma.

The researchers refused to go so far as to recommend that patients with asthma not be given the drug, but Dr. Barr did say more research into the problem was needed.

Acetaminophen is a widely used nonprescription analgesic sold under various brand names. It relieves mild to moderate pain and reduces fever. Often, it is taken in place of aspirin because it has fewer gastrointestinal side effects.

Asthma is a respiratory illness characterized by wheezing, difficulty in breathing, cough, and thick mucus production. It is caused by a spasm or inflammation of the bronchi. According to the authors, asthma prevalence has increased dramatically since the 1970s. The illness now affects five-to-eight percent of the U.S. population.

“Acetaminophen decreases glutathione levels in the lung, which may predispose persons to oxidative injury and bronchospasm,” said Barr. “Acetaminophen use has been associated with asthma in cross-sectional studies and a birth cohort.”

The authors noted that the large rise in the prevalence and severity of asthma in the U.S. coincided with a large increase in the use of acetaminophen in the 1970s and 1980s. They said that the switch from aspirin to acetaminophen was particularly pronounced among children following reports that linked Reyes Syndrome to aspirin in the early 1980s.

SOURCE: “Prospective Study of Acetaminophen Use and Newly Diagnosed Asthma among Women” by R. Graham Barr, et. al., American Journal of Respiratory and Critical Care Medicine, April 1, 2004.