Many aspects of pharmacotherapy in the treatment of borderline personality disorder also require investigation. Further controlled treatment studies of medications—in particular, those that have received relatively little investigation (for example, atypical neuroleptics)—are needed. Studies of continuation and maintenance treatment as well as treatment discontinuation are especially needed, as are systematic studies of treatment sequences and algorithms. The following are some specific questions that need to be addressed by future research:

• What is the relative efficacy of different pharmacological approaches for the behavioral dimensions of borderline personality disorder?
• What is the relative efficacy of different pharmacological augmentation and combination strategies, and what is their efficacy compared with treatment with single agents?
• How does the presence of certain clinical features (for example, prominent self-destructive behavior or dissociative features) affect response to pharmacotherapy?
• What is the minimal dose and duration of an adequate trial for different medications in patients with borderline personality disorder?
• What is the optimal duration of different types of medication treatment?
• What are the indications for discontinuation of effective pharmacological treatment?
• Are atypical neuroleptics or typical neuroleptics more effective or better tolerated in patients with borderline personality disorder?
• How efficacious are mood stabilizers for patients with borderline personality disorder, and which patients are most likely to benefit from this treatment? Are certain mood stabilizers more effective than others?
• What role should ECT have in the treatment of patients with refractory or severe borderline personality disorder?