Overview of nicotine replacement therapy​

Candidates for NRT

NRT should be recommended to all patients who are interested in quitting or cutting down on smoking.

The only contraindication for NRT is with patients who have current or recent acute coronary syndrome or patients who have had intolerable side-effects with NRT.

Clinical guidelines in Canada, the United States and Europe emphasize that primary care providers should encourage patients who smoke to use NRT in all its forms.

The U.S. guidelines include an excellent quick reference guide for clinicians, along with other useful resources for clinicians and patients (which are translated into Spanish) (2008 PHS Panel, 2008).

One study (Alpert et al., 2012), which has been widely reported in the media, challenges assumptions about the effectiveness of NRT when it comes to relapse rates. Read the response of CAMH scientists to this study.

Is nicotine dangerous?

Nicotine has not been shown to cause cancer, chronic obstructive pulmonary disease (COPD) or vascular disease.

It is the delivery system – the cigarette – not the drug that is responsible for the vast majority of tobacco-related disease. Major adverse effects from using nicotine gum or the nicotine patch are very rare.

Nicotine is a stimulant, like caffeine, and has the potential to stimulate the circulatory system, with an increased risk of arrhythmias and raised blood pressure. Thus, NRT is not recommended for patients with unstable cardiac disease – but then again, neither are cigarettes.

Smoking while on the patch

Despite the popular belief that smoking while on the patch can be dangerous, there is no evidence to suggest that it is any more dangerous than smoking alone.

Patients should be encouraged to not smoke on the patch. However, tell patients not to remove the patch if they have a cigarette or two. Such a step ensures failure because the blood nicotine level will begin to drop at the point when the patient is most vulnerable.

If a patient smokes while on the patch, ask how it felt. Feeling nauseous or shaky suggests that the dose of NRT is adequate. If the patient felt better, it suggests that the NRT dose may be inadequate. The dose can then be increased, or supplemented with nicotine gum or a nicotine inhaler.

Rationale for using nicotine in smoking cessation

Other than varenicline, there is no substitution drug for nicotine, but there are substitutes for cigarettes that are far less addicting. The patch allows patients to control their use of nicotine in a way that cigarettes do not.

It is the cigarette – the delivery system – rather than the nicotine itself that is responsible for morbidity and for increasing the risk of addiction.

Does NRT maintain the addiction?

NRT does not perpetuate the addiction, for the following reasons:

• The addictive potential of nicotine, as with all addictive substances, varies with the rate and route of nicotine delivery.
• The cigarette is a highly engineered and carefully designed nicotine delivery system. It is a far more addictive mechanism than nicotine gum or the patch because it makes a potentially addictive drug both far more rapidly available and convenient to repeatedly self-administer.
• Because nicotine from cigarettes is absorbed through the lungs, it takes only seven to 20 seconds for the drug to reach the brain – faster than an equivalent intravenous injection of nicotine. This rapid delivery results in a faster and more intense response, increasing the pleasurable feedback and thus, the risk of addiction.
• With the patch, nicotine levels in the blood rise over hours instead of seconds, resulting in a very slow onset of effects. As a consequence, the patch has very low addictive potential.
•  Immediate-release NRT (e.g., gum, inhaler, lozenge, spray) provides nicotine to the brain more rapidly than the patch but less rapidly than cigarettes. These agents have far less addictive potential than cigarettes.
• Using NRT maintains physical dependence on nicotine, but it does not perpetuate addiction. Addiction implies more than physical need for a drug: It implies loss of control of use of the drug.