SOURCES: Natalie Walker, Ph.D., associate director, Center for Addiction Research, University of Auckland, New Zealand; Nancy Rigotti, M.D., professor, medicine, Harvard Medical School, Boston; Dec. 18, 2014, New England Journal of Medicine
WEDNESDAY, Dec. 17, 2014 (HealthDay News) -- The naturally occurring plant compound cytisine may be more effective than nicotine replacement therapy in helping smokers quit, a new study suggests.
Cytisine, an acid-like chemical found in the seeds of the golden rain tree, has been used in Eastern Europe for decades to help smokers quit, researchers say. But it's not widely available.
"Cytisine is one of the most affordable smoking cessation medicines available," said lead researcher Natalie Walker, an associate director of the Center for Addiction Research at the University of Auckland in New Zealand.
"It is much cheaper than nicotine patches, gum and/or lozenges and other smoking cessation medicines," she said. "However, currently cytisine is only sold in a number of countries in Eastern and Central Europe. It is important that cytisine become more widely accessible and available."
For the study, Walker and her colleagues randomly assigned more than 1,300 men and women who called a national smoking quit line in New Zealand to 25 days of treatment with cytisine or eight weeks of nicotine replacement therapy with patches, gum and/or lozenges. All participants also received telephone support.
After a month, 40 percent of those taking cytisine pills said they hadn't smoked, compared with 31 percent of those who used nicotine replacement therapy, the researchers found.
The findings were published Dec. 18 in the New England Journal of Medicine.
Cytisine mimics nicotine so smokers get the same satisfaction as if they smoked, the experts said.
"To the brain, cytisine looks a little like nicotine, and so it works to alleviate any urges to smoke and reduces the severity of nicotine withdrawal symptoms," Walker explained.
"Plus, if you do smoke while using cytisine, it will be less satisfying -- making quitting easier," she said.
Cytisine was more effective than nicotine replacement therapy in helping smokers stay off cigarettes in the first week, and after two and six months, the researchers found.
However, cytisine can cause side effects, Walker said. "Three out of every 10 people who used cytisine had a side effect, compared to two out of every 10 that used nicotine patches, gum and/or lozenges," she said. The side effects didn't last long and weren't serious. "Some people felt nauseous or sick and some had sleep disturbances, such as bad dreams," Walker said.
Dr. Nancy Rigotti, a professor of medicine at Harvard Medical School and author of an accompanying journal editorial, said she supports cytisine's use as a smoking cessation tool.
"Cytisine is an old medication, and studies like this one have shown that it is effective," she said. "We need to find a way to make treatment of tobacco use accessible and affordable to all of the world's smokers."
The challenge, Rigotti said, is to figure out how to get cytisine licensed as a tobacco treatment in all countries, including the United States, while still keeping it affordable.
Tobacco use is the leading preventable cause of death worldwide, Rigotti noted.
"A majority of smokers now live in low- and middle-income countries," she added. "We have effective treatments to help smokers, but they are generally too expensive for smokers in low- and middle-income countries to afford."
For more about quitting smoking, visit the American Cancer Society.