Around 70 percent of current smokers want to quit. The health risks associated with smoking are well-known, but quitting smoking is a challenge because smokers are addicted to nicotine, experiencing unpleasant withdrawal symptoms when attempting abstinence. This problem has led to the creation of a wide variety of nicotine replacement therapy (NRT) products, which aim to help smokers quit by providing a dose of nicotine and thereby minimizing the withdrawal symptoms. There are many types of NRT, but nicotine patches and gums are the most common, with other options like nicotine inhalers also available.
History of Nicotine Patches and Gums
Nicotine replacement therapy was created more out of a desire to alleviate the irritation associated with quitting smoking among the navy in Sweden. Smoking on submarines was banned, and this was having an impact on the crews’ tempers on long trips at sea. The solution came from Ove Fernö, a scientist working for the pharmaceutical company Leo, who developed a nicotine gum which gradually released a dose of the drug. This first surfaced in 1967 for use in the navy, but soon the potential benefits of the approach became clear and it started to be sold to help smokers quit in 1978.
The nicotine patch didn’t surface on the market until 1992, invented by Dr. Murray Jarvik. Dr. Jarvik spent much of his career demonstrating that nicotine was the addictive agent in cigarettes, and using animal experiments to show that nicotine gum can be used to alleviate cravings. The idea for the patch came from his knowledge of “green tobacco illness,” which was a condition affecting workers who harvested tobacco. He theorized that nicotine was being absorbed through the skin and creating the symptoms, and after being denied permission to perform a test on somebody else, Jarvik and his student tested it on themselves. The idea was patented, and soon licensed to pharmaceutical company Novartis.
Types of Nicotine Replacement Therapy (NRT)
Nicotine gums – Nicotine gums are available in different strengths and flavors, and are used in a similar way to chewing tobacco. The gum is chewed for a short period, and then held between the inside of the cheek and the teeth so the nicotine can be absorbed. Common strengths of gum are 2 mg (milligrams) and 4 mg of nicotine, and users generally consume anything from 8 to 15 per day.
Nicotine patches – Nicotine patches are applied like a band-aid, and gradually release a dose of nicotine to the user over the course of a day (depending on brand this can be overnight or just while awake). These are available in different strengths, with NicoDerm, for example, offering 21 mg, 14 mg and 7 mg of nicotine.
Inhalers – Nicotine inhalers are small plastic devices which contain a cartridge of liquid nicotine, allowing users to suck on the end for a dose of nicotine in much the same way as smoking. These generally come in cartridges containing 10 mg of nicotine, but they only deliver 4 mg each. Most users consume anywhere from 6 to 20 cartridges per day.
Other NRT – There are also other types of nicotine replacement therapy, such as nasal sprays as lozenges. Lozenges work very much like gum, but they simply dissolve in the mouth, whereas nasal sprays are more fast-acting and are inhaled directly through the nose.
Health Concerns with Nicotine Gums and Patches
Although nicotine gums and patches (as well as other forms of NRT) are approved for use by the FDA, there are still some health concerns relating to their use. The concern is largely related to long-term use, but there have been concerns raised regarding many different conditions, including mouth cancer from nicotine gum usage and other issues such as insulin resistance and the potential for oral health issues. Additionally, there is some uncertainty with regards to the effectiveness of NRT for quitting smoking when used “over-the-counter.”
Cancers – Generally speaking, nicotine isn’t considered a cause of cancer, in fact, it’s the numerous carcinogens present in combusted tobacco which contribute to the increase in risk for various cancers seen in smokers. One piece of research from 2009 called this theory into question with regards to nicotine replacement therapy, however, proposing the possibility of oral cancer from nicotine gum due to nicotine’s effect on a specific gene. This caused some concern, but the finding is very limited and it’s unclear from the study alone whether it would contribute to increased cancer. Given the lack of increased risk of oral cancer in snus users (a form of smokeless tobacco, also containing nicotine and held in the mouth), it seems unlikely that NRT would involve a significant risk. Some researchers looked at this issue again with specific reference to NRT, and followed participants for five years. The researchers were able to determine that smoking was a predictor of cancer, as expected, but NRT was not, so overall it seems reasonable to conclude that nicotine patches and gums do not put users at risk from cancer.
Cardiovascular conditions – Nicotine is generally considered to have an impact on cardiovascular health, and this has been investigated with respect to NRT use too. A piece of research into the issue followed nicotine gum users for five years, and looked at whether its use (or the dosage) was related to cardiovascular deaths or hospitalization for related conditions. Side effects such as dizziness were commonly reported, but the researchers didn’t find any relationship with cardiovascular illness.
Other conditions – Researchers have also looked at the effect of NRT on conditions where use of NRT is potentially problematic (according to label guidelines), including heart disease, high blood pressure (not managed with medication) and diabetes mellitus. Half of the participants were assigned to nicotine gum and half to lozenges (which provide a higher dose of nicotine), and the researchers monitored reports of adverse effects. The findings show that nausea was the most common side effect, and less than 6 percent of the participants in each group had their condition get worse during the 12-week study period. Over 60 percent of participants saw no change in their condition at all during the study period. However, other research has suggested that nicotine contributes to insulin resistance and abnormalities associated with insulin resistance syndrome, and therefore NRT treatment should only be undertaken for a limited period of time.
Oral health – Other concerns about nicotine replacement therapy – especially gums – revolve around potential effects on oral health. One study investigating this issue split smokers into two groups, who were randomly assigned to either nicotine gum or a placebo gum, and the researchers monitored their oral health through examinations for issues such as plaque, gingivitis, tartar (calculus) and staining. The results showed that gum didn’t have a significant impact on dental health, but continued smoking led to an increase in tartar and gingivitis.
Pregnancy – The situation isn’t completely clear when it comes to the use of nicotine replacement therapy in pregnancy. What can be said for certain is that continued smoking is harmful to the infant, and as such nicotine replacement therapy is the preferable of the two options. However, with the potential risks to the developing baby associated with nicotine, the prudent advice is to avoid using gums, patches or other NRT when pregnant. Some research suggests that NRT use is justified in cases of a moderate to high level of addiction, but not if the individual smokes fewer than five cigarettes per day. This is merely because continued smoking is much more dangerous, so it’s worth taking a smaller risk if there’s no other way to remove the significant risk. In any case, this should always be discussed with a doctor, and any NRT use continually supervised.
Adverse effects – Plenty of research has looked into the potential adverse effects associated with NRT use, and generally speaking these have only found minor effects. For nicotine gum: mouth ulcers, nausea, jaw ache, hiccups, dizziness, headaches and insomnia were common, and these were more common in the users of 4 mg gums, who also experienced some indigestion. For nicotine patch users, many of the side effects are the same as for gums – headaches, nausea, dizziness, indigestion and insomnia – and are clearly related to nicotine itself rather than the specific form. Some unique side effects, such as skin irritation and abnormal dreams were reported, however. The abnormal dreams are a result of nicotine consumption during the night (which the body isn’t accustomed to), and are one reason patches are also available in a 16-hour form, so it can be removed during sleep.
Effectiveness for smoking cessation – One of the biggest questions relating to the use of patches and gums is how effective they are for their intended purpose. The Cochrane Collaboration conducted a systematic review of the evidence on the effectiveness of NRT for smoking cessation, looking at 132 studies in total. “Cold turkey” (attempting to quit without assistance) abstinence rates at six to 12 months are estimated to be between 3 and 5 percent. When NRT is used, the estimate based on the research to date is that 2 to 3 percent can be added onto this rate, suggesting a maximum effectiveness of 8 percent. A more recent piece of research investigated the effectiveness of NRT bought over the counter (without behavioral support), and found that in the absence of additional support, quit rates using gums and patches aren’t substantially different from “cold turkey” rates. In fact, if anything the research found that cold turkey quitters were slightly more successful than over-the-counter NRT users.