It is estimated that over 80% of patients with schizophrenia smoke. High rates of smoking may be related to decreased nicotinic acetylcholine receptors (nAChRs) in certain brain regions of patients with schizophrenia that are related to the illness but also create a drive for nicotine as a means to self-treat and even reduce symptoms of the illness including negative and cognitive symptoms. This can make quitting hard. Effective treatments include nicotine replacement therapy, bupropion, and varenicline. However, some people on varenicline have reported increased suicidal ideations. There is also evidence that contingent reinforcement (CR) with money may also be effective.