Ask the Experts: Is Long Term Use of Nicotine Replacement Therapies (Sprays, Gum and Patches) Harmful to Your Health?

We asked five public health and addiction medicine experts if long-term use of nicotine replacement therapies poses significant health risks. Their answers reveal important distinctions between nicotine itself and the thousands of harmful chemicals in cigarette smoke. From clinical researchers to behavioral scientists, these experts weigh in on whether continued use of nicotine gums, patches, and sprays presents meaningful health concerns for former smokers. The evidence might be more reassuring than you think.

Hayden McRobbie has answered Unlikely

An expert from Queen Mary University of London in Public Health, Behavioural Science, Clinical Research, Obesity

There are unlikely to be any adverse effects of using nicotine replacement therapy (NRT) long-term.

The majority of long-term NRT users are ex-smokers, who require the ongoing NRT use to keep them from relapsing back to smoking. Using NRT long-term is many times less harmful than smoking.

Karl Erik Lund has answered Unlikely

An expert from Norwegian Institute of Public Health in Public Health

The vast majority of the harm from smoking is caused by the burning of tobacco and not nicotine.  Despite being an established treatment, there is considerable worry among potential users and quit-smoking councilors regarding the safety of long-term NRT use, possibly due to misunderstandings about the role of nicotine separate from smoked tobacco. Studies find that long-term NRT use is safe and any associated health risks small, certainly compared with continued smoking. Only a small percentage of ex-smokers continue to use NRT beyond the standard length of 3 months so there are not many studies available. The medical consensus seem to be that long-term NRT appears to be a safe and effective way to reduce exposure to combustible nicotine. Long-term use of nicotine replacement therapy (NRT) has been approved in several countries for smokers who are unable or unwilling to quit smoking. Side effects from using NRT are related to the type of product, and include skin irritation from patches and irritation to the inside of the mouth from gum and tablets. There is no evidence that NRT increases the risk of heart attacks.

Tim Coleman has answered Extremely Unlikely

An expert from The University of Nottingham in Clinical Research

This answer relates to using nicotine replacement therapy (NRT) instead of smoking. This is the way that NRT is intended to be used. There may be some odd people out there who have started using NRT without actually being a smoker and this does not apply to them.

Tobacco smoke contains lots (thousands actually) of nasty cancer causing chemicals and toxins; it also contains carbon monoxide. Many of these substances are harmful (e.g. cause cancer). Nicotine is also present in tobacco smoke; although nicotine is addictive and fuels cigarette / tobacco addiction it seems otherwise relatively harmless.

Many, many research studies have shown that the long term consequences of tobacco smoking are dire. There are very few studies which have investigated the health impact of using nicotine long term but shorter term studies are reassuring and as NRT contains only nicotine without the thousands of toxins in tobacco smoke, it is not remotely possible that long term NRT use could be considered harmful when the alternative is continued smoking.

Mark G Myers has answered Unlikely

An expert from University of California, San Diego in Addiction

There have been few studies looking at long-term effects of nicotine or nicotine replacement. Those published find a) that nicotine does not increase likelihood of lung tumors, b) a long term study with rats (2-years exposed to high levels of vapor nicotine) find no difference between those exposed and not exposed on lung health, only difference noted that those exposed weigh less, c) an article that interviewed Dr. Richard Hurt at the Mayo Clinic and Dr. John Hughes at University of Vermont, both eminent scholars in smoking cessation both indicated that they do not believe there are any significant health risks to long term use of nicotine replacement. This would be consistent with my own observational experience of patients who quit smoking but continued using NRT for at least 2 years.

Note that nicotine does have acute effects on heart rate (increased) and causes short term vascular constriction, both of which can be a concern for individuals with heart disease or peripheral vascular disease, however from my reading of the literature, in general the relatively low levels of nicotine obtained from NRT don’t appear to significantly increase risk for cardiovascular events or wound healing.

Shellie Boudreau has answered Near Certain

An expert from Aalborg University in Neuroscience, Health, Motor Learning, Musculoskeletal Science, Communications Technology

Nicotine is a highly addictive substance and in its pure form can be lethal if too much is ingested. Nicotine replacement therapies, such as sprays, gum or patches aim to reduce the addictive properties by slowly releasing smaller doses of nicotine into the bloodstream. The amount released in nicotine replacement products is much less than a traditional cigarette. By way of the lungs, nicotine reaches the brain within the first minute when inhaled whereas replacement therapies take a longer time (e.g. 10 to 20 min). Indeed, the slower release helps curb the craving and does offer health benefits over the fast acting vapor or inhaled forms. However, application of nicotine to the oral tissues or small amounts has consequences. Swallowing small amounts of nicotine by way of chewing gum or tablets can lead to irritation of the mouth, throat and digestion system. Research shows that long-term exposure to nicotine can alter our sense of temperature in the mouth (https://doi.org/10.3389/fphys.2017.00663). Nicotine is a known irritant and when applied to the tongue, for example, can cause a burning sensation similar to a chili pepper. This is why many nicotine replacement products add cooling agents (i.e. menthol). Additionally, nicotine alters heart rate activity in ways we are only beginning to understand. It is well-established that cigarettes are a poor health choice due to the many additives however much less is known about nicotine exposure itself; especially when someone is exposed for long periods of time and repeatedly. In this case, one should rely on science to estimate the exact risks but until then a little common sense goes a long way. One only has to ask, why would you repeatedly expose yourself to a lethal and burning substance for a very long time?

Verdict: Most Experts Consider Long-Term NRT Use Safe, Particularly Compared to Smoking.

The experts have spoken: four of the five specialists view long-term nicotine replacement therapy (NRT) use as unlikely to cause significant harm, especially when compared to continued smoking. They emphasize that most health risks from smoking come from combustion products and thousands of toxins in tobacco smoke rather than from nicotine itself. One expert dissents, noting concerns about nicotine’s effects on the mouth, digestive system, and heart rate. While minor side effects like skin or mouth irritation may occur, most experts consider these insignificant compared to the dangers of returning to cigarettes.

As you can see, expert opinions on this topic show some variation, though most agree that for smokers trying to quit, long-term NRT use is far safer than returning to cigarettes. Find more research on nicotine, smoking cessation, and harm reduction strategies on Consensus, or explore the related questions below to dive deeper into this fascinating topic!