A woman smokes on a street in central Sydney April 7, 2011. Australia's government has unveiled plans for some of the world's toughest anti-smoking laws, saying it would force big tobacco companies to use plain green packaging for cigarettes despite the threat of industry legal action.

A woman smokes on a street in central Sydney April 7, 2011. Australia's government has unveiled plans for some of the world's toughest anti-smoking laws, saying it would force big tobacco companies to use plain green packaging for cigarettes despite the threat of industry legal action. Reuters/Daniel Munoz

A prescription drug designed to help people quit smoking was found to initially help women more than men, says a study from Yale School of Medicine. Researchers claim that varenicline, which is marketed as Chantix, is more effective in women than men.

The study's findings, which appeared in the journal Nicotine and Tobacco Research, revealed that varenicline was 46 percent more effective in women after three months of treatment and 31 percent more effective in maintaining complete abstinence from smoking after six months.

A smoking cessation agent, varenicline works in the brain by blocking the pleasurable effects of smoking. The drug appears to help smokers reduce the habit by making the activity less satisfying. Users are advised to take the two-pill-a-day treatment for 12 to 24 weeks.

“Studies show that women have a harder time quitting smoking than men, even as quitting has shown greater benefits to women’s cardiovascular and respiratory health. With this first comprehensive analysis of sex differences in the effectiveness of this drug, now women and their healthcare providers can better decide how to successfully quit and live longer, healthier lives,” said Sherry McKee, professor of psychiatry and lead researcher of Yale's Specialized Center of Research.

In the study, McKee’s team analysed clinical trial data from more than 6,000 smokers who used varenicline for smoking cessation. According to researchers, varenicline produced similar rates of smoking abstinence for men and women – 53 percent after three months. However, when they factored in the lower placebo effect in women, they found that varenicline increased the odds of women quitting by 46 percent.

While it is clear that sex differences in varenicline efficacy exist, McKee noted that they don't know the reason yet why the drug is particularly effective for women. However, she said that sex differences in the nicotine receptor system in the brain may be a key factor.

According to McKee, this is the first study to demonstrate that women compared with men have a preferred therapeutic response for a smoking cessation medication when considering short-term treatment and equal outcomes in one year. She added that varenicline appears to be particularly useful for reducing the sex disparity in smoking cessation rates.

Tobacco use is considered the leading cause of preventable death. According to the World Health Organisation, tobacco use causes nearly six million deaths worldwide per year, and current trends show that tobacco use will cause more than eight million deaths annually by 2030. Australia’s Department of Health reports that each year, smoking kills an estimated 15,000 Australians and costs AU$31.5 billion in social and economic costs.

Contact the writer at feedback@ibtimes.com.au or tell us what you think below.