In May 2018 researchers from the UK published their review of the medical scientific literature to assess the effectiveness and safety of nicotine replacement products, A total of 133 studies involving 22,581 individuals who used nicotine gum, 25,754 a nicotine patch, 4,439 oral tablets/lozenges, 976 a nicotine inhalator and 887 a nicotine nasal spray were included in the review. The individuals enrolled in the studies typically smoked at least 15 cigarettes a day at the start of the study. Results showed that all forms of nicotine replacement products (gum, transdermal patch, nasal spray, inhalator and sublingual tablets/lozenges) improved the odds to successfully stop smoking. In fact, the nicotine replacement products appeared to increase the rate of stopping by 50-60%. The effectiveness of the nicotine replacement products appeared to be largely independent of the intensity of additional support provided. A further analysis revealed that nicotine replacement products often caused minor irritation of the administered site and in rare instances individuals reported non-ischaemic chest pain and palpitations. All the studies analysed were assessed to provide high-quality evidence.
Hartmann-Boyce J et al. Nicotine replacement therapy versus control for smoking cessation. Cochrane Database Syst Rev. 2018 May 31;5:CD000146