Now there's a cure for the smoker's blues

A new anti-smoking pill, based on an anti-depressant, becomes available this month. And it seems to work

By nine o'clock this morning, 13 million people in Britain will have lit up their first cigarette of the day. And this year, just like every year for the past two decades, more than seven million of them will be trying to give up. But only one-in-20 will have any long-term success.

By nine o'clock this morning, 13 million people in Britain will have lit up their first cigarette of the day. And this year, just like every year for the past two decades, more than seven million of them will be trying to give up. But only one-in-20 will have any long-term success.

Despite counselling, aversion therapy, shock tactics, dummy cigarettes, nicotine patches, chewing gums and nasal sprays, smoking is almost as difficult to treat as the lung cancers it causes.

Although the chances of giving up may be greater than lung-cancer survival rates - only one per cent of advanced cases will be alive five years after diagnosis - it is an uphill struggle, with most people defeated by withdrawal symptoms. But a new non-nicotine therapy, based on an anti-depressant drug, could swing the odds in favour of reluctant puffers trying to give up, research showing success rates of up to 30 per cent.

Zyban, or bupropion, is being launched by Glaxo Wellcome in the UK (in pill form) later this month, and is expected to be a major player in the smoking cessation market. In the US, where it is already available, it is the most prescribed product for stopping smoking.

For several years, the only pharmacological approach to smoker's cold turkey has centred on several kinds of nicotine replacement therapy. Although it is only one of many chemicals that are inhaled by smokers, nicotine is the problem because it's addictive, activating the release of neurotransmitters such as dopamine and norepinephrine. Dopamine levels become elevated in areas of the brain that are associated with boosting the effects of compounds such as opiates, cocaine and amphetamines.

"The release of these neurotransmitters results in behavioural arousal, sympathetic neural activation, and a number of other effects believed to be rewarding. Nicotine is psycho-active and has a number of effects on mood," says Dr Linda Hyder Ferry, a specialist in non-nicotine approaches to stopping smoking.

For years the full effects of nicotine were not completely understood, but it is now known that not only does it have a major impact on the central nervous system, but that the effect is very swift. Researchers have shown that it takes only 10 to 18 seconds for nicotine to get from the cigarette to the brain.

While nicotine patches, nose sprays and gum help smokers to give up by providing an alternative source of the compounds, Zyban works in an altogether different way.

"The use of anti-depressants in smoking cessation has intrigued investigators for several reasons. Smokers are more likely to have a history of major depression than non-smokers, and nicotine may act as an anti-depressant in some smokers," says Dr Richard Hurt of the Nicotine Researcher Center at the Mayo Clinic, Minnesota, and co-author of the first major study on the effects of bupropion on giving up smoking.

There are other links between smoking and depression, too. The neurochemical effects of nicotine, including the release of dopamine, norepinephrine and serotonin, resemble the effects that some anti-depressant drugs have.

Two major research studies have shown that smokers using bupropion are more likely to give up smoking than by using nicotine patches. In one study, 30.5 per cent of people who had used bupropion were still not smoking 12 months later, compared to 16.4 per cent of nicotine-patch users. In the second study, 23 per cent of bupropion users were not smoking after 12 months, double the rate of those taking a placebo.

Although it is known that bupropion operates at the neurological level, reducing nicotine craving in any form, exactly how it works is not clear.

"It is thought to work centrally in the brain on the nicotine reward mechanism. When you smoke you get a charge out of nicotine, and if you want to calm down, it calms you down," says Dr Ian Campbell, consultant chest physician in Cardiff and a leading expert on smoke cessation methods.

Those who are prescribed Zyban will get two tablets a day, and the course of treatment will last seven to eight weeks. Treatment begins while the patient is still smoking, but with a target-date set for cessation, usually within the first two weeks.

If the patient has not reduced their level of smoking by the seventh week of therapy, it is unlikely that he or she will quit during that attempt.

Glaxo Wellcome were unable to give details of how much Zyban will cost when it is launched in the UK, but a seven-week course was yesterday being sold by an online US pharmacy for around £90, considerably less than the cost of a packet of cigarettes a day for two months.