Novel Pharmacotherapy Approaches in Smokers With Serious Mental Illness

Approximately 60 chronic smokers with bipolar disorder, schizophrenia or schizoaffective disorder who are motivated to try to quit smoking will be randomized to receive smoking cessation treatment with the FDA-approved medication, varenicline, delivered either a) at its standard dose and titration schedule (half of the participants) versus b) at a lower dose and slower titration schedule (the other half), for 12 weeks. All smokers will choose a target quit date sometime between 8 to 35 days after starting the medication. All participants will receive ten 30-minute sessions of a behavioral treatment called Acceptance and Commitment Therapy (ACT). Participants will be followed for an additional 12 weeks off study medication. The major endpoint is the feasibility of combining ACT with the different dosing strategies. Investigators will also conduct a blood test that measures the breakdown of nicotine in the body to explore whether that measure influences treatment response and side effects.