Borderline Personality Disorder (BPD) is the most common personality disorder which afflicts an estimated 2% of the general population, 10% of individuals seen in outpatient mental health clinics and 15–20% of psychiatric inpatients. Patients with BPD present a large variety of symptoms, high rates of comorbid conditions, substantial use of healthcare resources and constitute a significant social and economic burden. This disorder often is resistant to psychotherapeutic and pharmacological interventions. These therapeutic difficulties lead to common psychotropic drug prescription for BPD patients in clinical practice and, according to our results, in Spain virtually all patients with BPD are prescribed drug treatment and polypharmacy is common. It is possible that polypharmacy may also be a reflection of the severe difficulties encountered during the management of these patients. Another explanation could be the psychiatrist's ‘desperation’ due to the patients’ deterioration or lack of improvement, so that polypharmacy may be used to compensate the lack of funded and sustained psychotherapy programmes which would be required to successfully treat these patients in the long term.