Borderline Personality Disorder (BPD)

Aimee Aveyard
Author: Aimee Aveyard Medical Reviewer: Dr. Leila Khurshid Last updated:

Borderline personality disorder (BPD) is a mental illness characterized by an intense fear of abandonment, problems with self-image, and impulsive behavior. This disorder usually begins in adolescence or early adulthood. While causes are not well understood, it is thought that trauma, genetics and brain chemistry and development problems can all increase the risk. Medical professionals can treat it with different forms of therapy, and people with BPD may also be prescribed medication.

What is borderline personality disorder?

Borderline personality disorder is a mental illness that affects a person’s relationships and self-image and causes impulsive behavior. It is also known as emotionally unstable personality disorder (EUPD), emotional intensity disorder (EID), and borderline pattern personality disorder. It belongs to a group of diagnoses – personality disorders – which are all illnesses in which a person’s thoughts, emotions and behavior are different from those of the average person and significantly impact their quality of life.

Symptoms of BPD include a deep fear of abandonment, unstable relationships, problems with self-image, impulsive behavior, extreme anger, suicidal behavior, and self-harm.

Symptoms of borderline personality disorder

The main symptoms of borderline personality disorder are:

  • Intense fear of abandonment that can result in extreme attempts to avoid being abandoned
  • Difficulty in maintaining relationships and seeing relationships in very black-and-white terms – as either perfect or wholly bad
  • Insecure self-image, including a tendency to think of yourself as a bad person or even feel as though you don’t exist
  • Impulsive and self-destructive behavior such as substance abuse, overspending, or bingeing on food
  • Self-harm and suicidal thoughts and attempts
  • Intense emotions which can change rapidly, lasting from a few hours to a few days (swings from feeling very happy and positive to suddenly sad, anxious, or distressed)
  • Frequent feelings of emptiness
  • Extreme feelings of anger that are difficult to control
  • When stressed, paranoid beliefs and feeling dissociated (disconnected from yourself and your surroundings)

Diagnosing borderline personality disorder

According to the Diagnostic and Statistical Manual of Mental Disorders [1], used by mental health professionals in the U.S. to diagnose mental health problems, medical professionals can diagnose borderline personality disorder if a person meets at least five of the symptoms listed above. A diagnosis is made by a doctor or other mental health professional following a psychological evaluation, which includes a discussion of signs and symptoms, a review of medical history, and sometimes questionnaires.

A diagnosis of BPD can be difficult for some people to come to terms with. For others, it can be a relief to understand the underlying reasons for how they think, feel, and behave. In addition, a diagnosis can help unlock access to treatments such as therapy and medication.


The list of borderline personality disorder symptoms is also associated with other mental health conditions, which means people with BPD are often misdiagnosed. These conditions include:

A person can also experience BPD alongside other mental health problems, further complicating the diagnosis.

Misdiagnosis can be challenging. Feeling misdiagnosed can be difficult to cope with and set you down the wrong treatment path. If you think you have been misdiagnosed, discussing this with your doctor or mental health professional is essential.

Causes of borderline personality disorder

The causes of borderline personality disorder are not well understood. However, the main risk factors are trauma, genetics, brain chemistry, and development.


Trauma can result from several experiences, including physical abuse, sexual abuse, experiencing long-term distress as a child, parental neglect, losing a parent, and growing up in a family where there were mental health problems or substance misuse. Our childhood experiences, in particular our relationships with parents or caregivers, can shape how we view the world and our relationships with others.


There is no proof that a specific gene exists for BPD. However, research has suggested that genetics may play a part in putting some people at a higher risk of developing BPD. For example, you are more likely to be diagnosed with BPD if a close family member is also diagnosed. However, it’s unclear at this stage whether this is because of genetics or because people raised in the same environment often experience the same traumas and difficulties.

Brain chemistry

Research has found that some people with BPD have problems with their brain chemistry. Neurotransmitters – the chemicals that send signals between brain cells – play a part in controlling our mood and physical processes, including heart rate, breathing, and sleep. Research has found that abnormal levels of the neurotransmitter serotonin – a natural mood stabilizer – may be an underlying cause of BPD in some people.

Brain development

Researchers have also examined the brains of people with BPD using MRI scanners. MRI scans produce images of the brain that show where activity is taking place at different times. Scans have shown differences in the brains of some people with BPD, revealing either difference in size or levels of activity in three key areas:

  • The hippocampus is a part of the brain involved in memory, learning, and emotions
  • In the middle of the brain and next to the hippocampus, the amygdala affects emotions and memories that are linked to fear
  • An area in the prefrontal cortex, known as the orbitofrontal cortex, is an area of the brain believed to be involved in impulses and emotional reactions

Prevention of borderline personality disorder

Our current understanding of the causes of borderline personality disorder doesn’t give us simple ways to prevent BPD from developing. As with most mental health problems, prevention begins in childhood and relies on reducing the causes of poor mental health. These include traumatic childhood experiences, for example, and giving children the knowledge and tools to help them understand their emotions and talk about them with trusted adults who look after their well-being.

Treatment for borderline personality disorder

There is no known cure for borderline personality disorder, but medical professionals can successfully treat it. Treatment primarily includes psychotherapy and medication. The goal is to help minimize BPD symptoms, help you cope better with difficult thoughts and feelings and develop new ways to react and behave in response to triggering situations.


There are several different therapeutic approaches to BPD.

Dialectical behavior therapy (DBT)

Dialectical behavior therapy (DBT) is related to the better-known cognitive behavioral therapy (see below) and is designed specifically for people experiencing intense emotions. It helps with accepting feelings and improving reactions and behavior.

DBT is delivered in group or 1-2-1 settings and guides people with BPD through four key areas:

  • Mindfulness helps focus patients on the present and awareness of what is happening around and inside them without reacting to it
  • Distress tolerance, which is about learning to cope with difficult emotions without using self-harm or substances as coping mechanisms
  • Emotion regulation, to develop an understanding of what emotions are and techniques to regulate them
  • Interpersonal effectiveness includes practical ways to build and maintain healthy relationships with others

Mentalization-based therapy (MBT)

Mentalization-based therapy (MBT) helps us understand our thoughts and emotions and those of others. MBT is about questioning our thoughts and beliefs and exploring whether they are valid and based on fact. It also helps us understand how others behave, by exploring where their thoughts and ideas come from and questioning our assumptions about why people treat us the way they do.

Cognitive behavioral therapy (CBT)

Cognitive behavioral therapy (CBT) is a typical therapy for various mental health problems and may be helpful for people with BPD. It helps us understand the links between our thoughts, emotions, reactions and behavior and challenge negative thought patterns. CBT courses are often short, but clients leave therapy with practical tools to use in daily life.

Schema-focused therapy

A schema is a concept that allows us to take in and interpret information or circumstances. Schemas are developed from a young age and will enable us to define and understand things. For example, our schema for a chair might be that it generally has a seat, four legs, and a back – it’s how we know without consciously thinking about it that a chair is a chair. We also develop schemas about ourselves and our interpersonal relationships, which can be negative if we grow up in difficult circumstances. For example, if a parent abandoned us as a child, we may grow up believing that we are at a high risk of being left by anyone we love. Schema-focused therapy helps us to understand our schemas and the link between childhood experiences and how we react to situations in the present.

Systems Training for Emotional Predictability and Problem Solving (STEPPS)

Systems Training for Emotional Predictability and Problem Solving (STEPPS) is a 20-week course that draws on many the techniques and approaches listed above. The critical difference with STEPPS is that it involves not just the person with BPD but also their loved ones to help them understand the condition and support them to use the skills they learn once they leave therapy.

Transference-focused psychotherapy (TFP)

Transference-focused psychotherapy (TFP) is a type of psychodynamic therapy that, similar to others, looks at the underlying events and relationships from childhood that underpin how we think, feel and behave in the present. With TFP, the role of the therapist – and the relationship between the therapist and the client – is vital. It is based on the theory that a person’s feelings about their loved ones are transferred onto the therapist, which then allows the therapist to support them in developing better personal relationships.


The Food and Drug Administration hasn’t approved any medications to date for the specific treatment of BPD. However, medical professionals can prescribe several drugs to help manage particular symptoms or to treat co-existing mental health problems, including antidepressants, antipsychotics, mood stabilizers and sleeping pills.

Patients with BPD should only take medication for mental health problems with support and guidance from a professional and you should not stop taking the medication suddenly. Side effects can be significant and should be discussed with your doctor or a mental health professional before and during medication use.

Self-care for borderline personality disorder

As with most mental health problems, looking after your physical and psychological well-being is a good idea. Eating healthily, exercising regularly, developing good sleeping habits and avoiding stress can all go a long way in helping you stay well.

Here are some practical tips for dealing with the intense emotions associated with BPD, such as anxiety, anger, dissociation and the urge to self-harm:

  • Mindfulness: Short, guided mindfulness sessions can be found for free online. Taking just 15 minutes each day can help put some distance between you and your emotions, helping you feel less overwhelmed.
  • Grounding techniques: These can help at the moment with calming anxiety and intrusive thoughts by allowing you to focus on your body and senses. They include breathing exercises and other techniques, such as taking a few moments to note what you can smell, taste, hear and feel with your fingertips.
  • Distraction: Doing something you enjoy, like listening to music, watching your favorite show, getting creative with art supplies or getting outside to do some gardening, can help interrupt negative emotions and improve your mood.
  • Journaling: Getting your thoughts and feelings out of your head onto the page can help you process how you feel and allow you to spot patterns and triggers.
  • Talk to someone: Reach out to someone you trust and ask for a chat. Having someone else listen can help you feel validated and more able to cope.

Living with someone with borderline personality disorder

Living with someone with any mental illness can be challenging. If you are close to someone with borderline personality disorder, you may struggle to understand what they are thinking and how they are feeling. You may also find yourself on the receiving end of angry outbursts or the impact of their innate fear that you will abandon them.

There are many things you can do to support your loved one:

  • Look after yourself. It can be too easy to neglect ourselves when we trying to help someone else, but it’s crucial to make sure you look after your physical and mental well-being. Take time for yourself, do things you enjoy, eat healthily, stay active and get good sleep. If you are struggling with your mental health, seek help.
  • Read up. Learn as much as you can about BPD and how it affects people.
  • Creating a safe space for you both to talk about BPD and how it affects your relationship you have can help a lot. Make sure you listen, without judgment, to what they tell you about how they feel and what they are going through. Even if it is hard for you to understand, show them you care and are there to support them.
  • Get to know their triggers. If you both understand the circumstances that can trigger difficult emotions, you can work together on avoiding unnecessary difficulties and overcoming challenging situations.
  • Learn how to support them when they are struggling. For example, reminding them of good qualities when feeling negative, distracting them when they are anxious or reassuring them when they feel unsafe can help.
  • Maintain your boundaries. It’s important to remember that you can’t ‘fix’ them or save them from their mental illness. However, being clear and consistent about when you will be around and how much contact they can expect when you are apart can help you both feel safe and avoid becoming overwhelmed.
  • Encourage them to seek help – but don’t force them. If they are not ready to seek help, you need to accept that as their individual choice. But if they are willing, you can offer to research sources of support and go to appointments with them, for example.
  • Know what to do in a crisis. Research how to support someone who is suicidal or exhibiting self-harming behaviors so you know what to expect and how to react. If you are concerned that they pose an immediate risk to themselves or someone else, call your local crisis mental health service.

FAQs about borderline personality disorder

What is the outlook for someone with borderline personality disorder?

There is no absolute cure for borderline personality disorder, but it is treatable. People with BPD can and do recover with the proper treatment and support. Even if some symptoms persist, it is possible to reach a point where the impact on day-to-day life is minimal.

Why is it called borderline personality disorder?

The term ‘borderline personality’ has been around since the 1930s [2]. ‘Borderline’ refers to the fact that BPD symptoms didn’t fit neatly into the (now somewhat outdated) definitions that existed at the time.

How common is BPD?

According to the National Association of Mental Illness [3], borderline personality disorder is estimated to affect 1.4 percent of adults in the U.S. Around 75 percent of those diagnosed are women.

  1. Main, A. (2022, October 6). New Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. Generic.
  2. National Collaborating Centre for Mental Health. (2009). Borderline Personality Disorder: Treatment and Management. The British Psychological Society & The Royal College of Psychiatrists. Leicester, United Kingdom. Retrieved from
  3. Borderline personality disorder | NAMI: National Alliance on Mental Illness. (n.d.). Retrieved October 2, 2022, from
  4. Borderline Personality Disorder. (n.d.). National Institute of Mental Health (NIMH). Retrieved October 2, 2022, from
  5. NHS website. (2021, November 18). Symptoms – Borderline personality disorder. Retrieved October 2, 2022, from
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Aimee Aveyard
Author Aimee Aveyard Writer

Aimee Aveyard is a medical writer with 20+ years of experience in communications.

Published: Nov 8th 2022, Last edited: Sep 22nd 2023

Dr. Leila Khurshid
Medical Reviewer Dr. Leila Khurshid PharmD, BCPS

Dr. Leila Khursid is a medical reviewer with a Doctor of Pharmacy degree and completed a PGY1 Pharmacy Residency from St. Mark's Hospital.

Content reviewed by a medical professional. Last reviewed: Nov 9th 2022