Although no pharmacological treatments have received regulatory approval for borderline personality disorder (BPD), antipsychotic medications—particularly haloperidol, olanzapine, and risperidone—are frequently prescribed off-label in clinical practice. This study aims to quantitatively compare the efficacy of these three agents in the management of BPD. Moreover, considering the heterogeneous presentations of BPD among patients, the efficacy of these agents is also quantitatively compared in controlling individual symptom domains, including depression, anxiety, interpersonal challenges, cognitive impairment, impulsivity, and hostility. Due to the lack of head-to-head trials, indirect comparisons were conducted through a meta-analysis of effect sizes derived from open-label studies.