Review supports combination nicotine-replacement therapy for smoking cessation

By Nicole MacKee
Combination nicotine-replacement therapy (NRT) has again been found to be more effective than monotherapy for quitting smoking, but a smoking cessation expert says monotherapy is still the most common approach used in Australia.

Commenting on a recent Cochrane review of the doses, durations and modes of delivery of NRT, Associate Professor Colin Mendelsohn said the review was a timely reminder of the importance of optimising NRT, but the findings were not new.

‘Common practice, unfortunately, is to use a single agent,’ said Associate Professor Mendelsohn, a tobacco treatment specialist and Conjoint Associate Professor in the UNSW Sydney School of Public Health and Community Medicine. ‘We are always encouraging clinicians to use combinations because they work on both types of cravings – background and breakthrough – and they give bigger doses of nicotine.’

After evaluating 63 trials with more than 41,000 participants, the Cochrane reviewers found that using a nicotine patch together with another form of NRT, such as a lozenge or gum, increased the likelihood of successfully quitting smoking by about 25% compared with monotherapy.

Higher-dose NRT products were found to be more effective. Higher-dose nicotine gum (4 mg) was more effective than lower-dose gum (2 mg), and 25 mg patches (worn over 16 hours) and 21 mg patches (worn over 24 hours) were more effective than 15 mg (worn over 16 hours) or 14 mg (worn over 24 hours).

The researchers also found that ‘preloading’ (starting NRT products while smoking before quit day) could improve smokers’ likelihood of quitting, compared with commencing therapy on quit day.

Associate Professor Mendelsohn said even when used optimally, NRT provided only a modest increase in successful smoking cessation, and most patients used oral NRT products incorrectly.

‘People don’t use nicotine gum with the correct chew-and-park technique ... they just chew it like chewing gum,’ he said. ‘It’s important for clinicians to provide clear instructions on the correct use of oral products and to check it at each visit.’

Associate Professor Mendelsohn said patients should also be encouraged to use adequate doses of nicotine, as most users tend to underdose.

He said last year’s National Health Survey reported that 15.2% of Australian adults were still smoking, and that rate had barely changed in the past six years.

‘This is a big worry,’ he said. ‘We need to be optimising the treatments to give smokers the best chance of quitting.’
Cochrane Database Syst Rev 2019; (4): CD013308.