Doctors in France have been advised not to prescribe Zyban, the anti-smoking drug after an independent study found that the risks of taking it outweigh the benefits. The research found that convulsions, hypersensitivity reactions and insomnia are linked to Zyban use.

The drug has also been associated with a number of deaths. The British Government?s chief advisor on the safety of medicines, Professor Alisdair Breckenridge, said that many cases of adverse reactions have gone unnoticed and that the number of deaths and side effects could be ten times higher than the official figure. Zyban?s manufacturer GlaxoSmithKline said there is no evidence that Zyban had caused any deaths.