But despite the relative effectiveness of medications currently on the market, more than 80 per cent of quitters will be smoking again within a year, according to a review in the latest IJCP, the UK-based International Journal of Clinical Practice.
A new kind of drug has now been developed that could improve long-term quit rates, according to Dr Jonathan Foulds from the Tobacco Dependence Program at the University of Medicine and Dentistry of New Jersey.
Varenicline is being evaluated by the US Food and Drug Administration under a six-month priority review which began in late 2005.
"Trials carried out so far have yielded promising results, suggesting that varenicline could be a major advance in the treatment of nicotine dependence" says Dr Foulds.
"Drugs are normally earmarked for priority review by the FDA if they are felt to address health needs that are not currently being adequately met.
"What makes varenicline different to existing medication is that it is the first treatment specifically designed to target the neurobiological mechanism of nicotine dependence."
Initial results show that the drug successfully stimulates dopamine sometimes called the brain's pleasure chemical as well as blocking nicotine receptors. This reduces nicotine withdrawal symptoms and craving and may also prevent a lapse from turning into a full relapse.
Existing quit smoking methods have limited success and studies have found that some 18 per cent of people using them will be smoke free after a year, compared with 10 per cent of people prescribed placebos.
This figure can be increased to 25 to 35 per cent when smokers receive intensive counselling and combined medications are used.