Featured Review: Nicotine replacement therapy versus control for smoking cessation

High-quality evidence that all forms of nicotine replacement therapy can help increase chances of successfully stopping smoking.

Nicotine replacement therapy (NRT) aims to reduce withdrawal symptoms associated with stopping smoking by replacing the nicotine from cigarettes. NRT is available as skin patches that deliver nicotine slowly, and chewing gum, nasal and oral sprays, inhalators, and lozenges/tablets, all of which deliver nicotine to the brain more quickly than skin patches, but less rapidly than from smoking cigarettes. NRT aims to temporarily replace much of the nicotine from cigarettes to reduce motivation to smoke and nicotine withdrawal symptoms, thus easing the transition from cigarette smoking to complete abstinence.

A team of Cochrane authors based in New Zealand and the United Kingdom worked with the Cochrane Tobacco Addiction Group to determine the effectiveness and safety of NRT for achieving long-term smoking cessation, compared to placebo or 'no NRT' interventions.

136 trials were examined, with 64,640 people in the main analysis. All studies were conducted with people who wanted to quit smoking, mostly adults, with smokers typically having 15 cigarettes a day at the start of the study. The overall quality of the evidence was high.

The review found that all of the commercially available forms of NRT (i.e. gum, transdermal patch, nasal spray, inhalator, oral spray, lozenge and sublingual tablet) are effective as part of a strategy to promote smoking cessation. They increase the rate of long-term quitting by approximately 50% to 60%, regardless of setting. These conclusions apply to smokers who are motivated to quit. There is little evidence about the role of NRT for individuals smoking fewer than 10 to 15 cigarettes a day.

 “This updated Cochrane Review adds 18 new studies to when it was last updated in 2012”, says Professor Paul Aveyard, the Co-ordinating Editor of the Cochrane Tobacco Addiction Group. “The overall quality of the evidence is high, meaning that further research is very unlikely to change the conclusions.”

“This review provides those looking to quit the reassurance that nicotine replacement therapy works,” says Jamie Hartmann-Boyce from the University of Oxford and the primary author of the Review. “NRT is a safe and effective way to help people quit smoking, and taken individually all forms of delivery appear similarly effective. There is some evidence that taking a short-acting  form like gum alongside patch increases quit rates further – this is covered by a separate review which will be updated later this year.”