A change for the better

Pharmacists are perfectly placed to help people free themselves from tobacco addiction

Introduction

Tobacco use is the primary cause of preventable death in Ireland. Tobacco smoking harms nearly every organ in the body, with most tobacco-related deaths due to cancers, heart disease, and chronic obstructive pulmonary disease (COPD). Cigarette smoke contains over 4,000 chemicals, with at least 69 of these known to be carcinogenic. The Central Statistics Office reports that 16 per cent of people aged 15 years and over smoked either daily or occasionally, with a further 19 per cent having given up smoking. It was reported that 24 per cent of people aged 25 to 29 years smoked either daily or occasionally, which is the highest proportion among all age groups.

Therefore, smoking remains a significant health concern in Ireland. Smoking cessation is vital to reduce the burden on individuals’ health and on the healthcare system. Pharmacists are ideally placed as trusted healthcare professionals to play an important role in smoking cessation through patient education, pharmacological interventions, and non-pharmacological interventions.^1,2

Harmful effects of smoking

It is estimated that almost 6,000 individuals die in Ireland each year from tobacco-related diseases. The life expectancy of a long-term smoker is approximately 10 years less than that of a non-smoker. Smoking greatly increases the risk of developing cancer, with 90 per cent of lung cancers attributable to smoking. The quantity of cigarettes smoked and the duration of smoking correlate with an increased risk of developing lung cancer. Smoking also significantly increases the risk of other cancers such as mouth, throat, larynx, and oesophageal cancers, while also contributing to liver, pancreas, stomach, bladder, bowel, cervix, and kidney cancers.

Smoking damages the cardiovascular system by increasing heart rate, raising blood pressure, and reducing blood circulation, leading to a heightened risk of conditions such as coronary heart disease, myocardial infarction, stroke, peripheral vascular disease, and cerebrovascular disease. Smoking harms the respiratory system and can lead to respiratory disorders, including COPD, emphysema, pneumonia, worsening of asthma symptoms, and respiratory tract infections.

Smoking can also cause erectile dysfunction in men due to reduced blood circulation and can reduce fertility in both men and women. Smoking also delays the body’s recovery from surgery and infections. Smoking during pregnancy increases the risk of complications, such as miscarriage, premature birth, low birth weight, and stillbirth, while it is also associated with complications after birth including sudden infant death syndrome, infections, and asthma.^1,3,4

Pathophysiology of addiction

Nicotine may not be as dangerous as some other components in tobacco, but it is highly addictive. When tobacco is inhaled, nicotine enters the bloodstream via the pulmonary circulation, thereby avoiding first-pass and hepatic metabolism. It quickly crosses the blood-brain barrier. Nicotine then binds to nicotinic cholinergic receptors in the brain, with a half-life of approximately two hours. It activates the brain’s reward system, particularly in the ventral tegmental area of the midbrain, leading to a pleasurable feeling associated with smoking. This process results in the release of neurotransmitters, particularly dopamine, as well as noradrenaline, acetylcholine, and serotonin. After repeated exposure, nicotinic receptors may be upregulated and desensitised, leading to the development of tolerance. Furthermore, when nicotine levels drop, withdrawal symptoms  – including irritability, anxiety, and cravings – occur. These neurobiological mechanisms in the brain contribute to nicotine addiction.^5,6

Smoking cessation

Smoking cessation has both immediate and long-term health benefits, regardless of age or smoking history. It is one of the most important interventions a person can make to improve their health. There are immediate benefits to quitting smoking, observed shortly after cessation. These benefits include improved blood circulation, lowered blood pressure, decreased coughing, reduced phlegm production, and increased lung capacity.

Long-term benefits of smoking cessation include a reduced risk of developing various cancers, cardiovascular diseases, and respiratory conditions. The sooner a person stops smoking, the lower their risk of developing lung cancer. The benefits of smoking cessation are cumulative over time but stopping smoking at any age is advantageous. For example, quitting before the age of 40 reduces an individual’s chances of dying from smoking-related diseases by 90 per cent.

Additionally, even after a diagnosis of cancer or other smoking-related conditions, cessation can still offer significant health improvements. Despite the well-known benefits, smoking cessation is challenging due to the addictive nature of tobacco. Approximately 46 per cent of individuals who smoke have attempted to quit in the last 12 months, but only 25 per cent of these attempts are successful. Health benefits are often the primary motivation for individuals to quit smoking.^7,8

Treatment

Smoking cessation is recommended in all cases due to the numerous health benefits associated with it. Both pharmacological interventions and behavioural support can be highly effective in achieving cessation objectives. A combination of pharmacotherapy and non-pharmacological treatment options may yield the best results. An individualised management plan tailored to the patient’s needs and circumstances is the most effective approach for smoking cessation.⁷

Pharmacological treatment

Nicotine replacement therapy (NRT)

NRT is effective in helping individuals quit smoking, increasing the chances of quitting by 50-75 per cent. Discontinuing tobacco smoking can trigger withdrawal symptoms and cravings, which make cessation challenging. Withdrawal symptoms usually peak two to three days after quitting and can include mood swings, insomnia, diaphoresis, cognitive impairment, restlessness, and headaches.

NRT reduces the urge to smoke by providing the body with a safer form of nicotine. NRT products may contain a lower amount of nicotine than a cigarette and have a more gradual impact on the body. Furthermore, they lack many of the harmful carcinogens found in cigarettes. NRT is available in several different formulations, including patches, lozenges, inhalers, sprays, and gum. The choice of formulation may depend on patient preference. Combining different formulations may be beneficial, providing both background relief and breakthrough relief from cravings.

NRT is recommended to be initiated one to two weeks before quitting or immediately after discontinuing cigarette use. The quantity of cigarettes smoked per day and the time between waking and the first cigarette smoked should be considered to determine the appropriate NRT dose. Pregnant smokers should ideally quit smoking without NRT products. However, when the risk of smoking outweighs the risks associated with NRT, these products may be considered under the supervision of a physician. Common adverse effects of NRT include gastrointestinal discomfort, headache, palpitations, dizziness, and hypertension.⁹

Varenicline

Varenicline is another treatment option for smoking cessation. It acts as a partial agonist on nicotinic acetylcholine receptors, resulting in dopamine release in the brain’s reward centre, which reduces cravings and withdrawal symptoms. Additionally, it blocks nicotine from binding to these receptors, thereby reducing the pleasure derived from nicotine consumption. Varenicline is effective in achieving abstinence when used as monotherapy and may also be used in combination with NRT for greater efficacy.

The most common adverse effects of varenicline include nausea, constipation, insomnia, sleep disturbances, drowsiness, and headaches. Reports of neuropsychiatric effects, such as depression and suicidal ideation, have been noted with varenicline use. However, various studies have concluded that varenicline is not associated with an increased risk of suicidal ideation. Patients receiving varenicline should still be closely monitored for behavioural symptoms. Varenicline is renally excreted and therefore monitoring renal function is important. Due to limited safety data, varenicline is not recommended for use in pregnancy.^10,11

Varenicline is available as both 0.5mg and 1mg oral tablets, which should be administered with water to reduce gastrointestinal upset. Patients should set a quit date in advance, and varenicline should be initiated one to two weeks before this date. Treatment typically continues for 12 weeks, but an additional 12-week extension course may be considered for patients who have successfully stopped smoking. Lower doses may be used if adverse effects are experienced.^10,11

Bupropion is an atypical antidepressant used in smoking cessation. It exerts its mechanism of action as a norepinephrine-dopamine reuptake inhibitor (NDRI) and a nicotinic receptor antagonist. Bupropion inhibits the reuptake of dopamine and norepinephrine in the ventral tegmental area and the nucleus accumbens in the brain, thereby disrupting the reward pathways associated with nicotine.

Additionally, bupropion acts on nicotinic cholinergic receptors, reducing cravings and withdrawal symptoms. Bupropion is effective for smoking cessation when used as monotherapy but can also be used in combination with NRT, which is more effective than either treatment alone. The most common adverse effects of bupropion include headache, dizziness, weight loss, nausea, vomiting, and hypertension. Insomnia is a very common adverse effect but can be minimised by avoiding bedtime doses. More severe adverse effects include a lowered seizure threshold and the potential for worsening suicidal ideation. It is therefore not recommended for patients with a seizure disorder, and individuals with depressive symptoms should be closely monitored. However, bupropion is one of the few antidepressants that is not associated with sexual dysfunction. It is not recommended for use during pregnancy.^12,13

Bupropion should be initiated one to two weeks before the patient plans to quit smoking. The initial dose is 150mg once daily for six days, increasing on day seven to 150mg twice daily. It can be taken with or without food. Patients should be treated for seven to nine weeks, with treatment discontinued at week seven if no effect is observed. If the treatment is effective, it may be extended.^12,13

Non-pharmacological treatment

Behavioural interventions can be effective in increasing rates of smoking cessation. Behavioural interventions can be used as monotherapy or in combination with pharmacological treatment options. Multisession group therapy, intensive counselling on an individual basis, or advice from a healthcare professional can all be a part of behavioural interventions. Both minor and intensive in-person counselling sessions improve rates of smoking cessation, but more or longer sessions improve more cessation rates.

A combination of behavioural interventions and pharmacotherapy can greatly increase smoking cessations rates when compared with minimal behavioural interventions. All the pharmacological treatment options, including NRT, varenicline, and bupropion, are more effective when combined with counselling. Electronic cigarettes with nicotine have been used by individuals in recent years to attempt to quit smoking tobacco. However, there is not much information about the ingredients or long-term effects of electronic cigarettes. Therefore, they shouldn’t be recommended as a smoking cessation tool.⁷

Role of the pharmacist

Pharmacists can make a significant contribution to improving smoking cessation rates in Ireland. Pharmacists possess the expertise and communication skills to effectively counsel patients on the pharmacological treatment of smoking. This includes information on how to take the medications, potential adverse effects, the importance of adherence, and the duration of treatment. Furthermore, pharmacists can regularly offer motivation and behavioural interventions due to their accessibility in their community.

Evidence suggests that increased contact with a healthcare professional, including follow-ups, can enhance the success rate of smoking cessation programmes. Finally, pharmacists can refer patients to additional quitting services or specialised cessation programs as needed. Pharmacists can empower patients to overcome tobacco dependence by providing evidence-based pharmacological treatments, non-pharmacological interventions, and personalised care.