The researchers developed and tested a novel nicotine inhaler to see whether it helps smokers to quit smoking. Participants in the study were randomly assigned to receive either a nicotine inhaler plus a nicotine patch, or a placebo inhaler plus a nicotine patch.
The results of the New Zealand study funded by the Health Research Council appear in the journal Nicotine and Tobacco Research.
Study team leader Professor Julian Crane from the University of Otago, Wellington, says the findings are the first evidence that inhaled nicotine from a simple standard inhaler is highly effective and substantially increases a smoker's chances of quitting compared to the best current nicotine replacement treatment.
"Currently most smokers use nicotine patches to help them stop smoking. This study shows that if you add a nicotine inhaler to a nicotine patch, it doubles the chances of quitting over a nicotine patch alone," says Professor Crane.
Although there is considerable interest in the use of e-cigarettes to help smokers give up tobacco, many countries, including New Zealand, are hesitant to introduce these to the market especially as they are largely unregulated and untested.
"There is considerable debate about whether inhaled nicotine is helpful for people who wish to stop smoking," says Professor Crane.
"This is the first study to show that inhaled nicotine from a metered dose inhaler in the context of a smoker wanting to stop doubles their chances of quitting."
The nicotine inhaler gives a metered dose of nicotine and offers an alternative therapeutic option for inhaled nicotine using a standard device that has been used for many decades for treatment of asthma.
"But unlike electronic cigarettes, the inhaler has no physical associations to smoking itself," he says.
"It also has benefits in that it is much less likely to be used inappropriately to administer other drugs given that it is a completely sealed unit," notes Professor Crane.
"New Zealand has been a world leader in tobacco control public policy and this new home-grown development offers a world-first opportunity to help the 80 per cent or more of smokers who want to quit achieve their aims," he says.
The researchers are currently looking at how to make the inhaler available to all smokers who would like to use it.
Combination Nicotine Metered Dose Inhaler and Nicotine Patch for Smoking Cessation: A Randomized Controlled Trial. Nicotine and Tobacco Research. DOI:10.1093/ntr/ntw093. Published online May 16, 2016.