Conducted on 32,000 participants, this meta-analysis of placebo-controlled randomized controlled trials found that varenicline, nicotine nasal spray, bupropion (Wellbutrin), nicotine patches, tablets and gum helped people quit smoking.
But researchers said that "despite the documented efficacy of these agents, the absolute number of patients who were abstinent from smoking at 12 months was low."
In fact, they pointed out that varenicline was about twice as effective as bupropion.
They pointed out that there is a need to do more work for developing improved therapies to help people quit smoking and to "identify optimal cessation strategies, including alternative ways to use existing agents."
In a related commentary, Mayo Clinic researchers said that effective strategies to communicate options to stop smoking need to be developed.
"We are confident that the recommended treatments will substantially increase rates of smoking abstinence when given to smokers who wish to quit," yet there are barriers to these treatments.
The study also indicated an inability to translate and communicate research findings to the general population and laid stress on the need to develop better programs to disseminate smoking cessation therapies to smokers.
In a research letter, Dr. John Cunningham of Toronto's Centre for Addiction and Mental Health said that free nicotine replacement therapy could reap major benefits in helping people stop smoking. He writes this could have major policy implications.
The findings of the study appear in an article published in CMAJ.