Table 1.

Recommended cessation treatments for smokers

	Mode of action	Efficacy (vs placebo)	Recommended dosage	Duration of therapy	Major side‐effects	Cautions
Behavior interventions	Psychotherapy	Increasing quit rate by 40–60%	–	–	None	–
NRT	Desensitizing the nicotinic acetylcholine receptors and preventing them to resensitize	Increasing quit rate by 50–70%	(Gum) 4 mg about 8–12 times per day (Patch) 22 mg per day (Lozenges) at least 9 lozenges per day for the first 6 weeks	(Gum) at least 12 weeks (Patch) 8 weeks (Lozenges) no more than 12 weeks	Headache Nausea Vomiting Sore throat Hives Mouth ulcers.	Not recommended for: Pregnant smokers Smokers aged <18 years old.
Bupropion	Norepinephrine dopamine reuptake inhibitor A nicotinic receptor antagonist	Increasing quit rate by >80%	150 mg twice a day	12 weeks	Epileptic seizures Hypertension Increased risk of suicidal risk in smokers aged <25 years	Cautions for smokers with: Liver damage Severe kidney disease Severe hypertension.
Varenicline	Selective α4β2 nicotinic receptor partial agonist	More than double the quit rate	1.0 mg twice a day	12 weeks and may be continued for another 12 weeks if cessation is achieved	Mild nausea Headache Difficulty in sleeping Nightmares	Not recommended for: Pregnant smokers Smokers aged <18 years
E‐cigarette	Heating a liquid containing nicotine etc. to generate a vapor	No efficacy	Not recommended	–	–	–

NRT, nicotine replacement therapy; E‐cigarette, electronic cigarette.