For the public:
What is nicotine preloading?
Nicotine preloading means wearing a nicotine replacement therapy patch while continuing to smoke normally. In our research, people wore the patch for four weeks before they tried to stop smoking completely. We asked people not to cut down the amount they smoked while using the patch.
Why might preloading help?
Most people who smoke do so automatically, so when they come down for their morning cup of coffee, for example, they light up without thinking about it. This pattern of smoking is learnt by the brain because it comes to associate the hit of the nicotine in the cigarette with that situation (the morning coffee), sends a signal to smoke and this happens without a person needing to think about it. Every time someone smokes, the nicotine from the cigarette reinforces this learning. However, after an hour of not smoking, much of the nicotine in the brain that came from the cigarette has gone.
Nicotine patches release their nicotine steadily meaning that there is a constant and fairly high level of nicotine in a person’s system. When a person using a nicotine patch smokes, the nicotine coming from the patch blocks the extra nicotine from the cigarette acting in the brain. This means the act of smoking is unrewarding and the power of it is undermined.
What research did you do?
We tested whether nicotine preloading works to help people stop smoking. We worked with 1792 volunteers who all wanted to stop smoking and were prepared to give preloading a go. We split the volunteers into two groups randomly and one group used the patch for four weeks before trying to stop smoking while the other waited for four weeks. Using chance to decide who does and does not get preloading ensures this is a fair test- it means each group is as likely to succeed as the other. To help both groups stop smoking, people went to the NHS Stop Smoking Service. This service provides advice and techniques to boost people’s motivation and also provides medication, like nicotine replacement or tablet treatments, to make it less difficult to quit. Once they had tried to stop smoking, we checked on our volunteers’ progress 4 weeks, 6 months, and 12 months later.
What did you find?
At six months, 18% of people who used the preloading patch had stopped smoking, while 14% of those did not use preloading had succeeded. The results at 4 weeks and 12 months showed a similar pattern, a small advantage for the preloading group. There are two explanations for this difference. The first is that preloading caused an extra 3% of people to succeed and the second is that the difference arose due to chance alone. Chance means that in another similar test, we’d get different results, perhaps showing no advantage for the preloading group. We test this possibility using statistical tests and showed that chance could explain this advantage. This means in this test we did not produce enough evidence to be confident that preloading helps people stop smoking.
Is there a ‘but’?
Yes, there is. In this trial, people knew whether they were using the nicotine patch or simply waiting four weeks to quit and this affected what they did next. When people went to the NHS Stop Smoking Service, together with their stop smoking advisor, they chose a medication to help them after their quit attempt. Nearly everyone chose either nicotine replacement treatment or a tablet called varenicline, better known as Champix. The people who were preloading were more likely to choose nicotine replacement to help them after they tried to quit and less likely to choose varenicline compared with people who did not preload. Why does this matter? It matters because varenicline is more effective than nicotine replacement therapy, meaning that more people who use it stop smoking compared with those who had chosen nicotine replacement. This gave the non-preloading group an advantage. When we took account of this advantage, we saw that preloading gave a bigger boost to quit rates than in the first analysis, meaning about 4% of people stopped smoking because of the preloading rather than 3% without this adjustment. What’s more the statistics showed this was unlikely to be a chance finding.
This evidence that preloading might have been working is boosted by another finding in the study. We found that people who preloaded had lower cravings than people who didn’t preload. We saw lower cravings both while preparing to quit using the patch and, crucially, after a person tried to quit. This matters because we know that all effective medications reduce craving - that is how they work. This should give us confidence that preloading boosts quit rates.
Is it safe to smoke while on a nicotine patch? I thought you shouldn’t do that.
Yes, it is safe. We carefully assessed the side-effects of preloading compared with people just waiting to quit to see what problems they had. During the 4 weeks or so people were waiting to try to quit, some people were admitted to hospital or died. The same low number of people went to hospital or died in both groups. This tells us that these serious health problems were things that would have happened anyway and not caused by the preloading patch.
We also measured milder side-effects. About 2 or 3 in a 100 people got some nausea from the preloading with 1 in 100 vomiting because of it. 1 in 100 got headaches, vivid dreams, or poor sleep, all of which are known side-effects of the patch anyway. Overall, around 5 in 100 stopped using the patch because of side-effects, while 95 in 100 continued it.
This study shows its safe for people to use a nicotine patch while smoking and for the large majority this does not cause any side-effects either. Our study also backs up other research that shows that smoking while using nicotine replacement therapy is safe and supports the 2005 decision by the UK medicines regulator to remove warnings not to smoke and use nicotine patches at the same time.
What’s the bottom line?
Preloading, using a nicotine patch for four weeks before a quit day, can help a person succeed in stopping smoking but to achieve this benefit it is essential not to be put off using varenicline after a nicotine patch preload.
I want to stop smoking, what is your advice?
The way to boost your chances to the maximum is to do all three of these things:
- Go to an NHS stop smoking service. Getting support from a skilled professional will boost your chances.
- Use a nicotine patch preload for four weeks before your quit day.
- Start using varenicline 7-8 days before your quit day while you are still using a nicotine patch and continue it for 12 weeks usually or up to 24 weeks if you are struggling.
This is the best way but there are lots of other ways to try to stop smoking and here is a nice guide to them https://london.stopsmokingportal.com/.