Smoking cure has slimming side effect

Chemists have discovered a potential cure for smoking – inspired by cannabis's ability to make people hungry.

The new drug, called Rimonabant, has another potentially valuable side effect from the cannabis link: people who take the drug have not only been found to give up smoking, but they quickly lose weight as well.

In a month-long trial of 360 smokers who were trying to quit, Rimonabant's takers lost an average of 2.5lb in weight while a control group given a placebo drug gained more than 2.5lb in weight.

The creators of the new drug, the French pharmaceutical firm Sanofi-Synthelabo, believe that this effect will give their treatment the competitive edge over other treatments such as Zyban and nicotine patches.

Many smokers decide not to give up because they fear that their weight will mushroom, said Clive Bates, director of the anti-smoking charity Ash. "They fear that they will turn overnight into mad heifers," he said. "Most of these fears are exaggerated, but there's definitely a weight effect."

Rimonabant, which was originally designed as a treatment for obesity, works by targeting the parts of the brain which gives cannabis smokers the "munchies" – the powerful urge to eat. It blocks receptors in the brain which control that urge and which, at the same, heavily influence the body's craving for drugs such as nicotine, cannabis and even alcohol.

Sanofi-Synthelabo plans to launch it as an anti-smoking drug first in Britain and Germany in four years' time, and has started a new set of clinical trials of the drug which are expected to last up to two years.