While mental health professionals may use screening tools to help diagnose BPD, a single, definitive diagnostic test for borderline personality disorder doesn’t exist. Instead, a licensed mental health provider will diagnose BPD through a thorough assessment.

Diagnosis

If you suspect that you or a loved one has BPD, look for a mental health professional with experience diagnosing and treating personality disorders. Only a qualified mental health professional like a psychiatrist, psychologist, or clinical social worker can diagnose BPD. Usually, a diagnosis is made after a comprehensive assessment, which entails much more than a single test. The process may include consultations and conversations with previous caregivers, family members, and friends. A medical exam is often part of the assessment because it can help rule out other causes for the reported symptoms.

The Assessment Process

When you arrive for your first session with your new therapist, you may feel nervous or uncomfortable. Your therapist should share their diagnostic approach with you, but don’t hesitate to ask questions about what their assessment might entail. The assessment may carry over into a few sessions. That’s OK. Your therapist will ask you questions about your symptoms, health history, and life. You may be asked to complete a questionnaire or screening test. If you are diagnosed with BPD, your therapist will discuss recommended treatment options to help you manage your symptoms and feel better. As part of their assessment, mental health professionals may use screening tools to assist with diagnosis, including:

The McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD), which is a 10-item, paper-and-pencil test based on DSM-5 diagnostic criteria The Personality Diagnostic Questionnaire (PDQ-4), which offers another approach with 99 true or false questions that screen for several different personality disorders, including BPD

Professionals may also use resources like the APA’s Structured Clinical Interview for DSM-5 Personality Disorders to help screen for BPD.

Diagnostic Criteria

Ultimately, an official diagnosis requires at least five of the nine primary symptoms of BPD to be present:

Fear of abandonment Unstable and intense interpersonal relationships Uncertainty about self-image or identity Impulsive behavior Self-injurious behavior Emotional reactivity or instability Feelings of emptiness Difficulty controlling intense anger Transient suspiciousness or “disconnectedness”

Often, ordinary activities and events can precipitate symptoms in a person with BPD. For example, when a close friend or relative takes a vacation or has to cancel plans due to a work conflict, a person with BPD may become disproportionately upset and angry, fearing abandonment.

Causes

It is not yet known exactly what causes borderline personality disorder, but a combination of genetics, neurological, and social factors are most likely at play. For example, people with a first-degree relative who has the condition are about five times more likely to also have BPD. Additionally, many people with BPD experienced a past trauma that may have influenced the development of the disorder. Imaging studies have shown that people with BPD demonstrate structural and functional differences in their brains compared to those who don’t have BPD. 

Treatment

BPD treatment typically involves some combination of therapy, medication, and social support.

Psychotherapy

Therapy for BPD may include the following:

Cognitive behavioral therapy Dialectical behavioral therapy Psychodynamic psychotherapy

Medication

Medications may be adjusted over time based on trial and error and may include:

Antidepressants Antipsychotics Mood stabilizers

Lifestyle Modifications

In addition, adhering to some of the following lifestyle modifications may be useful in recovering from BPD:

Maintain a regular eating and sleeping scheduleExercise regularlySpend time with friends and family and build trusting relationships with people you can confide inInform friends, family, and co-workers about what may trigger symptomsBe patient with your progressLearn about your condition and stay informed about treatment optionsAvoid alcohol and drugs

A study published in the Journal of Affective Disorders found that BPD is a risk factor for bipolar disorder, and one-fifth of people with BPD also have a diagnosis of bipolar disorder. This comorbidity can make a diagnosis and effective treatment of BPD more difficult but not impossible.

A Word From Verywell

Borderline personality disorder is associated with a high risk of self-harm or suicide. If you or someone you know is exhibiting symptoms of BPD or any other mental illness, it’s important to talk to a doctor and get help. While there is no single test you can take to diagnose BPD, a licensed mental health professional can help determine whether your symptoms indicate BPD or another personality disorder and most importantly, recommend treatment that can improve your quality of life.