In this lesson, you will learn about the pharmacotherapy for smoking cessation. Many people know that smoking is bad for them. Yet, smoking remains the leading cause of preventable death worldwide. It's also interesting to note that less than one-third of smokers who tried to quit used proven smoking cessation treatments. So why aren't people utilizing treatment? One reason could be that health care providers are not engaging in smoking cessation efforts. Let's take a vote. The most common reason for lack of engagement is, lack of time, lack of expertise, or belief that efforts won't help. Sadly, time, knowledge and belief are all barriers. The good news is by the end of this lesson, you will see that it does not take that much time or know-how to recommend medications. Remember that rates of successfully quitting nearly double with the use of medications. So let's get started. We have seven FDA-approved medications for smoking cessation, including nicotine replacement therapies, or NRTs, bupropion and varenicline. Let us first look at the nicotine replacement therapies. There are multiple NRTs, including the patch, gum, lozenges, inhalers and nasal spray. These all offer full agonist activity at the nicotinic receptors and are started on the quit date and continued for up to 6 months. The patch comes in 21, 14 and 7 milligram doses. If the person smokes more than 10 cigarettes a day, we would recommend starting with the 21 milligram patch. We would continue this for 4 weeks, then decrease to 14 milligrams for 2 weeks, and then 7 milligrams for an additional 2 weeks. If the person smokes less than 10 cigarettes, we start with the 14 milligram patch for 6 weeks, and then the 7 milligram patch for 2 weeks. These are guidelines, and it's important to use your own judgment and tapering. For instance, it wouldn't make sense to switch to a lower dose if the person has not reduced or stopped their cigarette use. In this instance, we'd continue the higher dose and work on behavioral strategies to assist the person and their quit efforts. The patch is placed on the upper body above the waist and below the neck in a new location daily. Lozenges and gum come in 2 and 4 milligrams. The recommendation is the 2 milligram gum if the person smokes less than 24 cigarettes a day, and 4 milligram gum if more. The gum and lozenges can be taken every 1 to 2 hours and are particularly effective when used in combination with the patch. The patient should be instructed not to eat or drink for 15 minutes prior to or during use. The gum requires specific instructions of chew and park as the nicotine is absorbed through the oral mucosa. The patient needs to chew the gum until the flavor is released, and then park it along the gum line for the active ingredient to be absorbed. If the person choose the gum like regular chewing gum, then the nicotine will go to the gut, not be absorbed and likely cause some GI distress. Similarly, the lozenge should be placed in the mouth, allowing it to slowly dissolve with an effort to minimize swallowing so that, again, the active ingredient can be absorbed through the oral mucosa. The lozenge should not be chewed or swallowed. The inhaler involves a 4 milligram cartridge to be used every 1 to 2 hours. And the nasal spray is a dose of 0.5 milligrams. The patient should use 1 to 2 doses every 1 to 2 hours. So with all of these nicotine replacement options available, how do we decide? Given that the recommendation is a combination of NRT, if we're using NRT alone, the most common recommendation would be to use a patch for a long acting treatment, along with one of the other shorter acting forms for breakthrough craving. In patients with severe eczema or psoriasis, a patch may be contraindicated, in which case were then limited to only the short acting agents. Among the short acting agents, the inhaler should be avoided in those with bronchospastic disease. And the nasal spray should be avoided in those with underlying chronic nasal disorders or with severe reactive airway disease. If there are no contraindications to any of the available forms, then it's often about patient preference and availability of medication. Many patients do seem to prefer the gum and lozenge as it may address the behavioral and oral components associated with smoking. Beyond nicotine replacement therapies, we have two other medications to consider, bupropion and varenicline. Bupropion decreases craving and withdrawal symptoms. The mechanism of action is not entirely clear, but it works at the norepinephrine and dopamine receptors to inhibit reuptake, as well as it is an antagonist at the nicotinic acetylcholine receptors. Bupropion is started 1 to 2 weeks before the quit date at 150 milligrams daily for 3 days, and then increased to 150 milligrams twice a day. Bupropion works best if used in combination with nicotine replacement therapy, which would be started on the quit date. We continue this for 2 to 6 months, although if added for managing depressive symptoms as well, the medication may be continued even after the individual has stopped smoking. As with any medication, you will want to discuss potential side effects with patients and monitor closely. Bupropion had a black-box warning issued for neuropsychiatric symptoms, including suicidal thoughts. This medication also lowers the seizure threshold. So it's contraindicated in a person who has a seizure disorder or who may be at higher risk of having a seizure. Varenicline is the most effective single agent, although combination patch and gum is equally effective. It is a partial agonist at the nicotinic receptors and competitively inhibits the binding of nicotine. This partial activity allows for moderate dopamine release, minimal withdrawal from nicotine, and blocks nicotine so that smoking is less rewarding. Varenicline is started 1 week before the quit date and is titrated from 0.5 milligrams every morning for days 1 through 3, 0.5 milligrams twice a day for days 4 through 7, and then 1 milligram twice a day from day 8 onward. Of course, we can't forget side effects and monitoring. The most common side effect is nausea in up to one-third of patients, along with headache, insomnia and vivid dreams. If the target dose of 1 milligram twice a day is not tolerated, the dose can be lowered to 0.5 milligrams twice a day with still a very positive effect. Of note, varenicline had a black-box warning issued in 2010 for neuropsychiatric effects, but that has since been removed. In summary, we have nicotine replacement therapies, which are agonist, varenicline, which is a partial agonist, and bupropion, which is an antagonist. NRTs and bupropion are most effective when used in combination. And varenicline is the most effective single agent. There will likely be some trial and error involved. Remember too that while we are discussing pharmacotherapy here, that techniques including behavioral counseling, telephone support and self-help interventions are important adjunctive treatments that will improve outcomes. It is important to stay optimistic and instill confidence in your patient. After all, successful quitters have on average 7 unsuccessful attempts. You do not need to memorize all this material. There's a chart you can download in the resource section containing each medication we covered and its corresponding mechanism of actions, dose, side effects and contraindications.
