Varenicline in Bipolar Depressed Patients

Inclusion Criteria: * Age 18 -65 years * Meet DSM-IV criteria for bipolar disorder type I or II and nicotine dependence * DSM-IV confirmed current major depressive episode OR current depressive symptoms defined as MADRS \> 4 \& \<20 * Smoke at least 10 cigarettes per day * Fagerström Test of Nicotine Dependence (FTND) score of 5 or higher * Agree to identify collateral individuals for contact purposes to facilitate follow-up appointments * Currently on mood stabilization treatment. A minimum daily therapeutic dosage of at least one mood stabilizer, and on the same dose for at least 2 weeks: * Lithium (0.6-1.2 mEq/L or 900 mg), Valproate (50-125 mg/mL or 1000 mg), Carbamazepine (4-12 mg/mL or 800 mg), Oxcarbazepine 1200 mg, Lamotrigine 100 mg, Olanzapine 10mg, Risperidone 2mg, Quetiapine 300mg, Ziprasidone 40mg, Aripiprazole 7.5 mg * Antidepressants are not exclusionary. * Topiramate is an acceptable mood stabilization treatment. There is an evidence base (Delbello et al. 2005) highlighting efficacy of topiramate monotherapy for acute mania in children and adolescents with bipolar disorder type 1. \[Mood stabilizers are a standard American Psychiatric Association (APA) treatment guidelines for Bipolar I disorder (history of mania). While the guidelines for Bipolar II disorder are unclear (history of hypomania), we feel mood stabilization provides standardization of treatment and maximizes safety (ie: preventing switch from depression to mania or hypomania).\] Exclusion Criteria: * DSM-IV dependence for a substance other than nicotine or caffeine within past 3 months. * DSM-IV criteria of schizophrenia or other non-affective psychotic disorder * Psychotic symptoms within the past month * Active suicidality as measured by screening questions from the Columbia-Suicide Severity Rating Scale (C-SSRS * History of medically serious suicide attempt as reviewed by doctor. * Current use (past 30 days) of other smoking cessation treatments * Pregnant or nursing women, or women who refuse to use adequate birth control * Serious, active or unstable medical condition * Individuals, in the investigators opinion, unable to comply with study procedures * Inability to provide written informed consent in English * Allergic reaction to varenicline * Individuals who are on dialysis or have a history of kidney disease (varenicline is excreted 96% unchanged through the kidneys) or Creatine supplementation or current anticipated daily NSAID use * Presence of a personality disorder, that upon review of the medical record, appears to be the primary reason for psychiatric care.