Smoking Cessation Drugs: Bupropion, Nicotine Patches & Varenicline

As many smokers have experienced, quitting smoking can be an extremely challenging process. The combination of addiction to nicotine, maintaining a comforting habit, and confusion about the most helpful methods for quitting can lead many people who want to quit smoking to keep up the habit.

Much of the confusion about quitting smoking has to do with the various medications that are available to make it easier to quit. However, people don’t know much about how these medications work, whether they can truly help, or which one is most appropriate for the individual’s specific needs.

Different smoking cessation medications work in different ways, and they may or may not be helpful for a particular individual. Understanding more about these medications can help to clear the air about which path to take to quit smoking.

Nicotine Addiction

As explained by the National Institute on Drug Abuse, the source of addiction to smoking tobacco is nicotine – the chemical component that causes the heightened feelings of pleasure associated with smoking. This substance affects pleasure and reward pathways in the brain, regulated by the neurochemical dopamine, which heighten the desire to continue smoking. With repeated use of nicotine, this brain chemistry can be altered enough to result in addiction to smoking.

The Result of Excess Cigarette Use

There are multiple ways in which medicines can help a person stop smoking and start on the path to addiction recovery. These actions, and the medications that are used to create them, include:

  • Bupropion: a nicotine agonist that blocks the pleasure response, helping to reduce the desire to smoke
  • Nicotine replacement therapy: a programmed method of weaning the individual off smoking through measured, low doses of nicotine
  • Varenicline: a partial nicotine agonist that mimics the action of nicotine in the body to help eliminate cravings and withdrawal symptoms

Further information about each of these medications, including how they work, their effectiveness in addiction treatment, and risks of using them, is detailed below.


Bupropion was originally developed to treat depression. However, the Psychopharmacology Institute explains that this antidepressant also interacts with the chemical pathways in the brain that are affected by nicotine. In other words, bupropion interferes with nicotine’s effects on the dopamine system, as well as other elements of brain chemistry, which cancels the pleasurable effects of nicotine that create the desire to smoke. The brand of bupropion used to help people quit smoking is called Zyban.

A study of various smoking cessation methods from The Lancet demonstrates that bupropion does work better than a placebo in helping individuals abstain from smoking long enough to get the benefits of addiction treatment. However, drug information from the U.S. National Library of Medicine contains a warning that bupropion can cause people to experience disturbing psychiatric effects when the drug is used to quit smoking. These effects include:

These symptoms can mean that people who already have mental health disorders should not use bupropion. However, the drug has also demonstrated these effects in people who do not have a preexisting mental health disorder. For this reason, care should be taken when prescribing this medicine to help a person quit smoking.

Nicotine Replacement

Because nicotine is the addictive substance in cigarettes, the thought behind nicotine replacement therapy is that a person can easily wean off smoking by taking decreasing doses of nicotine over a period of time, as described by the National Library of Medicine. This is a common method of stopping any type of substance abuse or addiction, referred to as the “direct taper” method.

However, it is also preferred that people who smoke stop using cigarettes, cigars, or pipe tobacco as quickly as possible because there are other toxins in tobacco smoke that can cause damage to the lungs, heart, mouth, and esophagus, among other body systems. As a result, nicotine replacement is formulated to deliver this taper without the person having to continue smoking. The various methods of delivering the nicotine include:

  • Gum or lozenges
  • Nasal sprays or inhalers
  • Skin patches

According to the study in The Lancet, this method is similar to bupropion in its ability to help people stop smoking. However, risks of using nicotine replacement include increased nicotine toxicity if the person smokes while on the therapy. In addition, other studies – such as one from Evidence Based Medicine – indicate that stopping smoking abruptly may be more effective than trying to taper down.


Varenicline, also known as Chantix, was developed specifically as a medicine to help people quit smoking. This medication works by activating the brain’s natural nicotine receptors, giving the person the sensations that would normally be caused by nicotine. However, it also interrupts the response of nicotine in the brain, so if the individual smokes, no pleasure response occurs.

According to The Lancet, varenicline is more likely than either bupropion or nicotine replacement to help people stop smoking. However, it also has some major issues, including evidence that it interacts negatively with alcohol, increasing intoxicating effects and even potentially causing seizures. Similar to bupropion, it can also result in mood problems or changes, including anger, hostility, and depression.

Other Issues with Using Medications to Quit Smoking

Aside from the health and side effect issues listed above, using medications to stop smoking can be an issue because medication is not a guarantee that the person will stop craving nicotine. Particularly with nicotine replacement, the substitution of nicotine in another form may simply prolong the process of quitting, and it has already been shown that quitting abruptly may be more likely to result in recovery than a gradual taper.

Recently, a study from the Journal of the American Medical Association questions whether nicotine replacement and varenicline are truly any more helpful than other methods in stopping smoking. The study showed that 12 weeks of treatment with a nicotine patch, varenicline, or combination nicotine replacement therapy resulted in no significant differences in abstinence rates after 26 weeks. Combined with the evidence that abrupt quitting results in better outcomes, the effectiveness of medicines for quitting smoking is called into question.

Help in Quitting Smoking

There are other ways to help people quit smoking. Whether alone or in combination with the medicines discussed above, a research-based program that includes therapy and peer support is more likely to help individuals develop the tools and confidence to quit smoking and maintain abstinence. Working with an experienced treatment professional or program is the first step in stopping smoking for the long-term and enjoying a healthier future.

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