Nonsmokers diagnosed with depression had their symptoms relieved by taking doses of nicotine, Physorg.com reported Sept. 11.

Researchers at Duke University Medical Center gave nicotine or placebo patches to a group of nonsmokers diagnosed with depression, then measured their symptoms using a standardized questionnaire. They found that who wore the nicotine patch for at least 8 days experienced significant declines in depressive symptoms.

The authors said that while the findings showed that nicotine may have some medical benefits, the research should not be seen as encouragement for depressed people to start smoking. "The hope is that our research on nicotine will spur the development of new treatments for depression, which is a huge public-health problem," said lead researcher Joseph McClernon, Ph.D., of the Duke Center for Nicotine and Smoking Cessation Research. "Our study also provides evidence that smokers may indeed smoke, in part, to improve their mood -- a notion that has been quite controversial in the field."

"The same areas of the brain that are stimulated by nicotine appear to be involved in the regulation of mood," noted McClernon.

"Smokers may be more prone to depression than nonsmokers," added senior study investigator Edward Levin, Ph.D., "or, people with depression may be self-medicating by smoking, albeit in a deadly way."

Past research has shown that people with depression are more apt to be smokers.

The research appears in the online edition of the journal Psychopharmacology and will be published in print in November 2006.