ATC Group: N07BA Drugs used in nicotine dependence

Cytisine is a plant alkaloid with a chemical structure similar to nicotine. The use of cytisine allows for a gradual reduction of nicotine dependence by relieving withdrawal symptoms. The action of cytisine is similar to that of nicotine, but in general weaker. Cytisine competes with nicotine for the same receptors and gradually displaces nicotine due to its stronger binding.

Nicotine, the primary alkaloid in tobacco products and a naturally occurring autonomous substance, is a nicotine receptor agonist in the peripheral and central nervous systems and has pronounced CNS and cardiovascular effects.

Varenicline binds with high affinity and selectivity at the α4β2 neuronal nicotinic acetylcholine receptors, where it acts as a partial agonist – a compound that has both agonist activity, with lower intrinsic efficacy than nicotine, and antagonist activities in the presence of nicotine.