4.10.5 Cigarette smoking

ChoiceDrugDosage
Drug treatments should be offered as part of a programme of behavioural support

1st choice

Nicotine Replacement Therapy (NRT) -

Available in a choice of formats, see BNF


Dose:

See BNF or product SmPC
Or
Varenicline f/c tablets 500 micrograms, 1mgDose:
Start usually1-2 weeks before target stop date, initially 500 micrograms once daily for 3 days, increased to 500 micrograms twice daily for 4 days, then 1mg twice daily for 11 weeks (reduce to 500 micrograms twice daily if not tolerated); 12 week course can be repeated in abstinent individuals to reduce risk of relapse
Or
2nd choiceBupropion hydrochloride 150mg m/r, f/c tabletsDose:
Start 1-2 weeks before target stop date, initially 150mg daily for 6 days then 150mg twice daily (max single dose 150mg, max daily dose 300mg; minimum 8 hours between doses); period of treatment 7-9 weeks; discontinue if abstinence not achieved at 7 weeks; consider max 150mg daily in patients with risk factors for seizures; elderly max 150mg daily

Prescribing Notes

General Notes

  • People who want to stop smoking should be informed how to access local smoking cessation services, see want2stop.info .
  • Refer to NICE CKS Smoking Cessation for comprehensive smoking cessation advice, including details of drug therapies
  • Refer to NICE NG92 Stop smoking interventions and services, March 2018
  • Useful resources and training materials are available from NCSCT
  • A ‘Pregnancy and NRT’ patient information leaflet is available here to support pregnant women who smoke
  • The use of single or combination NRT together with a structured stop smoking programme should be regarded as the ‘gold standard’. However, choice of product should be based on patient preference, patient history, discussion of potential side-effects, consideration of co-morbidities, potential drug interactions and cost
  • Combination NRT (a patch plus a short-acting preparation) or varenicline have been shown to be the most effective treatments
  • An individual’s response to certain medication, particularly long-term medicines, may change as a result of stopping smoking, this may present as greater efficacy or response or more adverse effects.
  • 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.
  • If the person wishes to use e-cigarettes, they should be advised to use a licensed stop smoking medicine instead. However, if the person prefers to use e-cigarettes, they should be given information about these and support:
    • 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
    • The evidence suggests they are substantially less harmful than smoking but safety concerns remain and evidence is still developing e.g. long term health impact
    • For further information see BMJ

Nicotine Replacement Therapy (NRT)

  • 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
  • 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
  • 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)
  • 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
  • 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 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