Bupropion (Zyban) has been launched by Glaxo Wellcome as an aid to smoking cessation. It is available as a prescription-only medicine on National Health Service prescription. At the launch on June 26, Dr Gay Sutherland (lecturer, National Addiction Centre, Kings College, London) said that, with 97 per cent of smokers failing to give up using will-power alone, more treatments for smoking cessation were "desperately needed".
Dr Howard Marsh (senior medical advisor, Glaxo Wellcome UK) said that bupropion was the first non-nicotine prescription medicine licensed in the UK to help people stop smoking (see PJ, June 17, p933). He explained that it worked differently to nicotine replacement therapies (NRT) in that it acted as a dopamine and noradrenaline reuptake inhibitor to break the cycle of addiction. Dopamine was implicated in cravings and noradrenaline in withdrawal symptoms. Clinical trials involving 1,500 patients published last year in the New England Journal of Medicine (1999;340:685) had shown bupropion to be twice as effective as NRT, Dr Marsh said. The results had shown that 30 per cent of patients who had taken bupropion (300mg/day) were not smoking after one year compared with 16 per cent of patients using NRT patches (21mg/day).
While combining bupropion treatment with NRT had been shown in the trial to be more effective than bupropion alone (35 per cent and 30 per cent, respectively, of patients not smoking after one year), this was not a statistically significant difference, said Dr Marsh. Bupropion was not licensed for use in combination with NRT and it was recommended that bupropion should be used alone. It was also possible that combining the treatments could raise blood pressure. The effect of combining the treatments could be investigated in the future, he said. Dr Lew Pliamm (lecturer, University of Toronto and director, Quit clinic, Ontario, Canada) added that bupropion had been used in Canada for some time and, in his experience, heavy smokers sometimes used both forms of treatment. The same mechanism of action was addressed from two different angles, as both nicotine and bupropion caused the release of noradrenaline and dopamine, he said.
Dr Marsh explained that bupropion should be taken at a dose of 150mg once a day for three days and should then be increased to 150mg twice a day for the rest of the two-month course. Treatment should be started while the patient was still smoking and a "stop date" should be set for the second week. This was because it took five to seven days for the drug to reach steady state, he explained. The side effects of the drug were mostly mild and transient. The most common adverse effects were insomnia, dry mouth and headache. There was no evidence of dependence with bupropion, Dr Marsh said.
Dr Chris Steele (general practitioner and medical director, Stop Smoking clinic, University hospital of South Manchester) said that 40 per cent of smokers would not live to retirement age and that one in two smokers would be killed by smoking. The development of bupropion was a "major medical milestone" in the treatment of smoking cessation, he said. It provided a "new and entirely different approach to smoking cessation". However, he cautioned that, when prescribing bupropion, identification of patients who were motivated to stop smoking was essential. The most effective approach for motivated quitters was to combine pharmacological treatment with a support mechanism, he said.
Patients taking a course of bupropion will be given the opportunity to join a "Right Time" support programme. This includes a telephone helpline, action plan and mailings throughout the course of treatment to provide support. A two-month course of bupropion (recommended course seven to nine weeks) costs £85.70.