Cytisine is a chemical known ever since the sixties as a treatment for tobacco smoke cessation. It is an alcaloid present in a plant, Cytisus
laburnum, which acts as a partial agonist of the α4β2 nicotinic receptors of acetylcholine (nAChRs). The first studies were conducted in the
Eastern European countries and showed a good efficacy profile, but even then the marketing of the drug in the Western countries was limited
by European norms. Pharmacological studies show a brief half-life of the product, which is eliminated by the kidneys at 90-95%. Recently,
many clinical trials brought attention to cytisine, which showed a better efficacy for tobacco smoking cessation higher than placebo and than
nicotine, between 8% (12 months) and 22% (6 months) depending on the studies. The adverse effects mainly reported were disorders of the
digestive tract (nausea, dyspepsia, dry mouth, insomnia, or headaches). An important factor is the fairly low cost of the drug. In 2014, NHS
produced a document which evaluates the cost efficacy rate of pharmacological therapies for smoke cessation, concluding that cytisine has a
favorable profile with respect to other considered drugs.
