A REVIEW OF EVIDENCE AND AN ALGORITHM FOR USE OF PSYCHOPHARMACOLOGY IN THE TREATMENT OF TOBACCO USE DISORDER IN BEHAVIORAL HEALTH SETTINGS

Tobacco Use Disorder (TUD) represents a major and persistent public health problem and is disproportionately prevalent among individuals with psychiatric illness. Despite its substantial contribution to morbidity and mortality, TUD is frequently under-addressed in behavioral health settings, in part due to clinician uncertainty regarding psychopharmacologic complexity, psychiatric safety, and treatment sequencing. This presentation introduces a new, evidence-derived psychopharmacology algorithm for the treatment of TUD developed through the Psychopharmacology Algorithm Project at the Harvard South Shore Program. The purpose of this presentation is to provide psychopharmacologists and psychiatric clinicians with a structured, clinically actionable framework for medication-based treatment of TUD that integrates efficacy, safety, comorbidity-specific considerations, and treatment resistance. The content synthesizes findings from randomized controlled trials, meta-analyses, systematic reviews, and previously published algorithms to support rational pharmacologic decision-making in complex behavioral health populations. Methodologically, the algorithm was developed through a targeted PubMed literature review of English-language pharmacotherapy studies, including efficacy and safety trials, followed by qualitative expert consensus and iterative refinement through blinded peer review. The algorithm is intended as a heuristic to guide clinical judgment rather than a rigid guideline. After confirmation of TUD and readiness for pharmacotherapy, the algorithm prioritizes evaluation of comorbid conditions that may alter medication selection, including major depressive disorder, bipolar disorder, other serious mental illnesses, posttraumatic stress disorder, alcohol use disorder, cardiovascular disease, seizure risk, and concerns regarding post-cessation weight gain. Key findings to be presented include evidence supporting consideration of bupropion as an initial treatment option in patients with comorbid depression, while generally avoiding antidepressants in bipolar disorder and exercising caution or avoidance in individuals with seizure risk. In the main treatment pathway for cigarette smoking, varenicline is established as the most effective first-line pharmacotherapy, with combined nicotine replacement therapy as a second-line consideration when varenicline is contraindicated or declined. Criteria for adequate varenicline trials, dose adjustments, side-effect management, and evidence-informed augmentation strategies, including bupropion, are detailed. The role of combination therapy, such as varenicline plus nicotine replacement, is reviewed in the context of mixed and limited evidence. For users of smokeless tobacco, available data also support varenicline as the preferred first-line agent. Management of common adverse effects across pharmacotherapies is addressed. The presentation concludes with a discussion of emerging and investigational treatments with less established evidence but potential future promise. The clinical importance of this work lies in equipping behavioral health clinicians with a coherent psychopharmacologic roadmap that supports ownership of TUD treatment, improves cessation outcomes, and reduces tobacco-related morbidity and mortality among patients with mental illness.