Prescribing Notes
General Notes
- Tell people who smoke that a range of interventions are available to help them stop smoking. People who want to stop smoking should be informed how to access local smoking cessation services, see stopsmokingni.info.
- Offer advice on using nicotine-containing products on general sale, including over-the-counter nicotine replacement therapy (NRT) and nicotine-containing e-cigarettes.
- Refer to NICE CKS Smoking Cessation for comprehensive smoking cessation advice, including details of drug therapies.
- Refer to NICE NG209 ‘Guideline on tobacco: preventing uptake, promoting quitting and treating dependence.’
- Useful resources and training materials are available from training.cancerfocusni.org and NCSCT.
- A ‘Pregnancy and NRT’ patient information leaflet is available to support pregnant women who smoke.
- When combined with behavioural support, varenicline or a combination of short-acting and long-acting NRT or nicotine-containing e- cigarettes are more likely to result in successful stop smoking.
- Choice of product should be based on patient preference, health and social circumstances, potential side-effects, consideration of co-morbidities, potential drug interactions and their previous experience of stop-smoking aids.
- Nicotine releases catecholamines which can affect carbohydrate metabolism. Smokers with diabetes should be advised to monitor the blood sugar levels more closely than usual when attempting to quit smoking (with or without NRT).
- Stopping smoking may result in slower metabolism and a consequent rise in blood levels of drug catalysed by CYP1A2 (and possibly CYP1A1). This is because the inhalation of induction agents such as polycyclic aromatic hydrocarbons has stopped. There are a few drugs for which this is clinically significant, e.g. warfarin, theophylline, olanzapine and clozapine. Refer to SPS website for further details.
Nicotine Replacement Therapy (NRT)
- A combination of short-acting and long-acting NRT should be used when NRT is purchased or prescribed.
- The use of NRT preparations in an individual who is already accustomed to nicotine introduces few new risks and is widely accepted that there are no circumstances in which it is safer to smoke than to use NRT.
- Do not prescribe NRT with varenicline or bupropion.
- Side-effects such as hiccups or GI symptoms are more of a problem with buccal administration. Acidic drinks such as coffee, carbonated or fruit drinks should be avoided for at least 15 minutes before gum or lozenges are taken as they can interfere with absorption.
- Moderate to severe hepatic impairment and/or severe renal impairment decreases the clearance of nicotine or its metabolites and NRT should be used with caution.
- See BNF/ SPC for full prescribing details.
Varenicline
- Varenicline should not be used in patients under 18 years old or in those that are pregnant or breastfeeding.
- Do not prescribe varenicline and bupropion together.
- Varenicline should be prescribed with caution in patients with a history of cardiovascular disease or psychiatric illness. However, reports of depression, agitation, behaviour changes, suicidal ideation have not been substantiated in trials.
- Varenicline should be used cautiously in patients with a history of seizures or other conditions that potentially lower the seizure threshold.
- See BNF for full prescribing details.
Bupropion
- Bupropion treatment is less likely to result in successful stop smoking, than the first choice options.
- Do not prescribe varenicline and bupropion together.
- Bupropion is contra-indicated in patients with a current or previous seizure disorder, diagnosis of bulimia or anorexia nervosa, severe hepatic cirrhosis, history of bipolar disorder, pregnancy, breast feeding, and caution advised in heavy alcohol intake.
- Bupropion should be prescribed with caution in people with a predisposition to seizures including those taking other drugs which lower the seizure threshold (e.g. antipsychotics).
- Cases of serotonin syndrome have been identified in association with bupropion, especially in overdose or when bupropion is administered with other drugs with a serotonergic effect. See MHRA.
- Drug interactions are a significant problem with bupropion; see BNF.
- Bupropion should not be used in patients under 18 years old or in those that are pregnant or breastfeeding.
- See BNF for full prescribing details.
Nicotine Containing E-cigarettes
- E-cigarettes are not licensed as a medicine by the MHRA but are regulated by the Tobacco and Related Products Regulations (2016).
- E-cigarettes have been shown to be a useful aid to smoking cessation, however, 80% of patients continue to vape, unlike the minority who continue on NRT after stopping conventional cigarettes.
- There is not enough evidence to know whether there are long-term harms. Use is likely to be substantially less harmful than smoking although any smoking is harmful, so people using e‑cigarettes should stop smoking tobacco completely. For further information see BMJ.
- Any side effects or safety concerns should be reported via the Yellow Card scheme. See this page from the MHRA for further information on e-cigarette regulations and reporting.