Many people with borderline personality disorder (BPD) receive medical treatment. However, there are no drugs available for BPD treatment specifically. A certain drug is most often chosen because of its known properties in the treatment of associated disorders, or BPD symptoms that are also known to be present in other conditions, such as depressive, psychotic, or anxious disorders. BPD itself is characterised by a pervasive pattern of instability in affect regulation (with symptoms such as inappropriate anger, chronic feelings of emptiness, and affective instability), impulse control (symptoms: self-mutilating or suicidal behaviour, ideation, or suicidal threats to others), interpersonal problems (symptoms: frantic efforts to avoid abandonment, patterns of unstable relationships with idealization and depreciation of others), and cognitive-perceptual problems (symptoms: identity disturbance in terms of self perception, transient paranoid thoughts or feelings of dissociation in stressful situations). This review aimed to summarise the current evidence of drug treatment effects in BPD from high-quality randomised trials.
Available studies tested the effects of antipsychotic, antidepressant and mood stabiliser treatment in BPD. In addition, the dietary supplement omega-3 fatty acid (commonly derived from fish) which is supposed to have mood stabilising effects was tested. Twenty-eight studies covering 1742 study participants were included.
The findings tended to suggest a benefit from using second-generation antipsychotics, mood stabilisers, and omega-3 fatty acids, but most effect estimates were based on single study effects so repeat studies would be useful. Moreover, the long-term use of these drugs has not been assessed. The small amount of available information for individual comparisons indicated marginal effects for first-generation antipsychotics and antidepressants.
The data also indicated that there may be an increase in self-harming behaviour in patients treated with olanzapine. In general, attention must be paid to adverse effects. Most trials did not provide detailed data of adverse effects and thus could not be considered within this review. We assumed their effects were similar to those experienced by patients with other conditions. Available data of the studies included here suggested adverse effects included weight gain, sedation and change of haemogram parameters with olanzapine treatment, and weight loss with topiramate. Very few beneficial effects were identified for first-generation antipsychotics and antidepressants. However, they may be helpful in the presence of comorbid problems that are not part of BPD core pathology, but can often be found in BPD patients.
There are only few study results per drug comparison, with small numbers of included participants. Thus, current findings of trials and this review are not robust and can easily be changed by future research endeavours. In addition, the studies may not adequately reflect several characteristics of clinical settings (among others, patients' characteristics and duration of interventions and observation periods).