Melatonin May Worsen Asthma

Popular Supplement Could Leave You Breathless

From the WebMD Archives

Oct. 9, 2002 - Melatonin, a popular sleep aid often used to treat jag lag, may worsen asthma, according to a new study. And, it doesn't seem to take much to cause an effect - even small amounts of the supplement could cause problems.

Asthma is a disease of the lungs characterized by inflammation and tightening of the airways. People with asthma struggle with breathing and symptoms may be worse at night.

Melatonin is a naturally-occurring hormone produced by our bodies. Its popularity as a supplement is based on its ability to regulate sleep patterns, but scientists also have found that it can have an effect on inflammatory diseases such as asthma. Melatonin can cause the release of body chemicals that provoke inflammation.

Although it is not FDA-approved as a sleep aid, millions of people report using melatonin. At least some of these folks are likely to have asthma, a condition affecting some 17 million Americans.

Monica Kraft, MD, and colleagues from the National Jewish Medical and Research Center and University of Colorado Health Sciences Center in Denver examined the effects of adding melatonin to cells from people with asthma. They found that it significantly increased the release of inflammatory chemicals. Increased airway inflammation is the hallmark of worsening asthma. In addition, they found the effect especially pronounced at night, when people usually take melatonin.

Although the findings are preliminary -- only 23 people were included in the study -- the researchers suggest that people with asthma lay off melatonin until more is known about the hormone's effect. "For these patients, avoidance of melatonin may be appropriate until further information about the clinical effect of melatonin in asthma becomes available," they write.