China, the world's largest tobacco-consumption market, is working to extinguish smoking with new fervency, as a growing number of people view it as a major social issue.

But questions arise about which methods help people quit and which are simply smoke in mirrors.

Discussions are peaking on World No Tobacco Day on May 31. Last month, 118 Chinese scientists and professors signed an appeal to ban science and technology awards for tobacco technologies.

Controversy has also surrounded discussions about whether or not medical insurance should cover smoking-cessation initiatives, including medical advice and products.

Taobao, China's largest online retail platform, offers more than 30,000 quit-smoking aids. They include electronic cigarettes, herbs, chewing gums, toothpastes and even perfumes.

The country's 320 million smokers have also made it the world's largest smoking-cessation market, as public health awareness grows.

About 68 percent of China's smokers - about 220 million people - have tried to quit, the Chinese Association on Tobacco Control says.

But the report finds most smokers and experts agree that quitting smoking relies more on willpower than medical assistance.

China has about 800 smoking-cessation centers. But most are more like e-cigarette shops.

"These aids are useless," says smoking-cessation specialist Liu Xianyong with the First Hospital of Tsinghua University.

"They can't do anything to stop the craving that arises when a smoker stops."

Willpower, exercise, isolation from smokers, and support from family and friends are most effective, she adds.

But anti-smoking aids can reduce withdrawal symptoms and increase success rates if used under professional direction, experts say.

There are two kinds of mainstream anti-smoking medications in China - nicotine replacement therapy (NRT) and non-nicotine medicines.

Nicotine is tobacco's addictive chemical but not its most harmful. Tar, carbon monoxide and other substances are what cause most health problems.

NRT gives the body progressively smaller nicotine doses to slowly reduce cravings, vice-director of Beijing Hospital's respiratory department Ke Huixing says.

Common forms of the therapy recommended by the World Health Organization are the patch, the gum, the lozenge, the inhaler and the spray.

But NRT's long-term effectiveness isn't clear, some international studies suggest.

"They may cause skin irritations," Liu, the smoking cessation specialist, says.

NRT doesn't need a prescription. But a prescription is required to buy non-nicotine medications, such as nicotine receptor partial agonists and antidepressants.

Nicotine receptor partial agonists block the brain's reception of nicotine, but also enable nicotine receptors to release reduced amounts of dopamine.

Chantix, a prescription medication marketed by Pfizer, became the first nicotine receptor partial agonist approved by the US Food and Drug Administration in 2006.

An antidepressant, marketed under the brand name Zyban, is also used as an anti-smoking drug.

"Such drugs are effective, but they must be used under guidance," says Ke, the respiratory disease and smoking-cessation specialist.

People with a personal or family history of psychiatric illness should not take such medications, Ke says.

The drugs have been reported to cause depression, suicidal thoughts, changes in behavior, hostility and agitation.

The two most popular anti-smoking drugs have carried warnings about the risk of severe mental illnesses in the US since 2009, at the FDA's request.

They aren't printed with such warnings in China.

"All medicines have side effects," Ke says. "Side effects' risks must be weighed against the significant health benefits of quitting smoking. China has such a vast population of smokers. Quitting is the first priority."

Contact the writers through liuzhihua@chinadaily.com.cn