Distinguishing BPD from ADHD


Both borderline personality disorder (BPD) and attention deficit hyperactivity disorder (ADHD) are common among young people. 

BPD is a neurodevelopmental disorder characterised by a shifting sense of self, impulsive behaviours, and unstable relationships with others. ADHD, also a neurodevelopmental disorder, is identified by inattention, hyperactivity, and/or impulsivity.

While the core symptoms of the two conditions are very different, traits of both BPD and ADHD can cause young people to behave in similar ways. ADHD and its related features can have a wide effect on many domains of life, including emotional regulation and dopamine deficiency. Some young people also live with both BPD and ADHD. In these cases, it’s necessary not only to differentiate between symptoms but also to understand how the two conditions may interact and influence each other.

Effective diagnosis requires in-depth assessments and interviews that help a clinician understand the complexities of a young person’s feelings, behaviours, and relationships with others. With these insights, mental health professionals can design and deliver the best treatment for them, supporting young people to manage symptoms and build fulfilling futures.

Differentiating Symptoms of BPD and ADHD

While almost all of the symptoms of BPD can resemble symptoms of ADHD, they’re often rooted in thought patterns or emotions. This means that distinguishing BPD symptoms from ADHD often involves understanding why a young person is feeling or behaving a certain way. 

In this blog, we outline the nine symptoms of BPD, as listed in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). We explore how and why people with ADHD may exhibit similar symptoms – and how we can distinguish them.

1. Frantic efforts to avoid real or imagined abandonment


Young people with BPD often have an intense fear of being abandoned by others. They may find the process of separation incredibly distressing and hold a deep fear of being alone. As a result, individuals with BPD often try to avoid real or imagined abandonment at all costs.

Driven by a fear of abandonment, young people with BPD can go to great lengths to maintain relationships, engaging in elaborate or extreme behaviours. At other times, they may remain detached and avoid intimacy to prevent attachments from forming in the first place.

Sometimes, young people with BPD may suddenly and preemptively end a relationship when they think that the other person may leave. In many cases, the threat of abandonment is only imagined. This can lead to patterns of unstable relationships and, unfortunately, cause relationships to end prematurely. 


Some young people with ADHD also experience a sensitivity to perceived abandonment and/or a fear of being alone. However, for individuals with ADHD, these feelings are rooted in a fear of boredom – a state they can find particularly uncomfortable or distressing.

Young people with ADHD often struggle to feel engaged and stimulated when they are alone and may spend time with others to avoid feelings of boredom. These social interactions can help people with ADHD feel present in a given moment and prevent a sense of dysphoria.

Unlike individuals with BPD, if a young person with ADHD is feeling engaged and stimulated, they may not make the same efforts to hold on to relationships. At these times, their concerns about abandonment can fade and they may feel more secure in relationships.

2. A pattern of unstable and intense interpersonal relationships


Without effective support, young people with BPD often have unstable and intense relationships. They may experience patterns of idealisation and devaluation, sometimes seeing their partner as perfect and at other times thinking they are completely awful.

This type of dichotomous thinking, known as ‘splitting’, is common in young people with BPD. They may see themselves, other people, or things around them in black and white – as all good or all bad – and struggle to maintain a cohesive worldview where there are shades of grey.

It’s not completely clear why people with BPD see the world this way. Some researchers think it’s to do with an inability to mentalise, the act of understanding the mental state that lies behind someone’s actions. Young people with BPD may also use splitting as a coping mechanism, switching to patterns of idealisation and devaluation in response to threats of abandonment or other emotional distress.


Young people with ADHD may also experience patterns of idealisation and devaluation in relationships, especially with romantic partners. However, these feelings and behaviours are caused by changes in stimulation, rather than black-and-white thinking.

Some researchers think that the lack of dopamine in the brains of young people with ADHD means that they are chemically wired to seek more. This means that it can be very difficult for them to accept or stay in situations where they are not sufficiently stimulated. Instead, they may constantly seek situations that trigger a more intense release of dopamine.

At the start of a friendship or romantic relationship, someone with ADHD may feel excited and stimulated by getting to know the other person, experiencing new things, and feeling intense emotions. As the relationship progresses and their experiences become more routine, they may start to feel less engaged. At this point, they may switch from idealisation to devaluation, deciding that the other person can no longer fulfil their needs.

While some young people with ADHD experience interpersonal difficulties, they are not usually as consistent or as severe as the experiences of people with BPD. In fact, many individuals with ADHD have strong and stable relationships with others.

3. Markedly and persistently unstable self-image or sense of self


Young people with BPD often don’t have a clear sense of who they are. They may find that parts of their identity are frequently and suddenly changing, such as their interests, hobbies, friend groups, goals, and aims. They may also have an unstable perception of their own value, switching between high and very low self-esteem.

Some people with BPD try to find a sense of self through relationships with other people. When they become close to a certain person or group, they may feel like the relationship makes up a big part of their identity, giving them a sense of grounding. They may have ‘chameleon’ tendencies, forming interests, goals, and aims that fit in with those around them.

People with BPD often struggle with chronic feelings of emptiness or feelings that they do not exist. These feelings can be especially strong when they are alone.


Unlike young people with BPD, teenagers and adolescents with ADHD usually have a strong and stable sense of their core identity. They may struggle more with the way their sense of self, interests, and goals fit in with the world around them.

Some people with ADHD struggle to settle on a niche that feels ‘right’ for them or find a place where they fit in. They may also have difficulties completing tasks or maintaining focus and interest when something takes a long time. This can cause them to change their interests and hobbies more often than other people.

4. Impulsivity that may be self-damaging


People with BPD often act impulsively. They may spend money recklessly, drive dangerously, abuse substances, or binge eat.

Sometimes, a young person with BPD may use impulsive behaviours as a coping mechanism that grounds them or distracts them from emotional distress. Impulsivity can also be caused by a lack of mentalisation, causing a young person to act according to impulses, urges, and feelings, without considering where the impulse might come from or what consequences an action may have.


Impulsivity in young people with ADHD is very similar to BPD. Young people with ADHD may act impulsively to try and ground themselves or escape from intense feelings of unease or distress. 

With ADHD, this unease can be caused by a lack of dopamine in the brain. When this happens, young people may seek the dopamine high of certain impulsive behaviours to relieve themselves from unpleasant and dysphoric feelings.

5. Recurrent suicidal behaviour, gestures, or threats, or self-mutilating behaviour


Around 60% to 70% of people with BPD attempt suicide at some point during their lives. 

Some people with BPD may think that they don’t want to be alive or have a desire for death because they feel like they are not made to live in this world. They may struggle with chronic feelings of numbness and emptiness, lacking any grounding or sense of purpose. They may also experience intense emotions that can feel unbearable.

Self-harm is also common among young people with BPD. Self-harm can be a form of self-punishment that results from self-hate or low self-esteem. It can also be a way for young people to relieve themselves from dissociative states and feel more ‘real’ or more ‘here’.


Suicide is more common in people with ADHD than in those who are not living with the disorder.

Young people with ADHD may be at a greater risk of suicide because of their impulsivity, making it more likely that they will act when they feel strong feelings or urges. Individuals with untreated ADHD may also struggle to navigate important aspects of daily life, such as school, work, and relationships with others. They may experience feelings of loneliness, failure, and hopelessness that can make suicidal thoughts more likely.

Suicide Prevention

If you or a young person you know is not coping with life, there is help and support available. You can call Papyrus from the UK on 0800 068 4141 or visit their website here for confidential suicide prevention advice. If you think someone’s life is in immediate danger, call an ambulance as soon as you can.

6. Affective instability due to a marked reactivity of mood 


Young people with BPD often experience intense moods that last from a few hours to a few days. They may feel dysphoric, irritable, anxious, despairing, or other strong emotions.

These mood changes may happen in response to both internal and external triggers. Internal triggers include mental states, thoughts, and feelings, such as a feeling of emptiness or struggles with identity. External triggers could include interpersonal difficulties or the threat of real or imagined abandonment.


Young people with ADHD may also experience mood changes, but they are usually less rapid and intense than the mood instability seen with BPD. Shifts in mood tend to be caused by external triggers rather than internal feelings.

7. Chronic feelings of emptiness


Many young people with BPD experience recurring feelings of emptiness. Feelings of emptiness can be very distressing and may be a cause of self-harm or suicidal behaviours. For some people, chronic emptiness may relate to an unstable sense of self or a lack of meaningful connection with others.


When someone with ADHD is lacking in stimulation, they may also experience feelings of boredom or emptiness. However, these feelings are not usually chronic and tend to go away if they find something that engages them. The feeling of emptiness may also have a different quality to that experienced by young people with BPD.

8. Inappropriate, intense anger or difficulty controlling anger


Young people with BPD often experience intense anger. They may express their feelings through frequent displays of temper, constant anger, or recurrent physical fights.

People with BPD may feel angry when they feel like someone close to them isn’t giving them the care or attention they need. They may also feel intense guilt and shame after displays of anger, seeing themselves as a ‘bad’ person as a result of black-and-white thinking.


ADHD is linked to deficient emotional self-regulation, including low frustration tolerance, temper outbursts, and mood instability. This means that young people with ADHD may react with intense anger to small triggers and have difficulty remaining calm.

Unlike BPD, however, ADHD anger is usually a normal response to a certain event, even if it is more intense than other people may experience. 

9. Transient, Stress-Related Paranoid Ideation or Severe Dissociative Symptoms


Young people with BPD may experience episodes of paranoia or dissociation, where they feel disconnected from their body, thoughts, and the world. Dissociation is often a coping mechanism for extremely distressing situations, causing an individual to detach from the reality that they are facing. In individuals with BPD, dissociation is usually transient and most often occurs in response to threats of real or imagined abandonment.


While inattentiveness in young people with ADHD may sometimes look like dissociation, they are usually experiencing a very different mental state to the dissociation that characterises BPD.

Some young people with ADHD may zone out or become lost in their own thoughts, disconnecting from the present moment. However, they remain connected to something internal or external, such as a thought or their bodies. The experience of dissociation, on the other hand, describes a complete disconnect from everything: their body, thoughts, and reality.

Treating BPD and ADHD

Without effective treatment, both BPD and ADHD can make navigating daily life difficult for young people. Sometimes, it can feel almost impossible. The good news is that there is plenty of support available that’s proven to help young people with each disorder manage symptoms and lead fulfilling lives. 

Treatment for ADHD may include medication and psychotherapy, such as cognitive behavioural therapy. Young people with BPD may benefit from dialectical behavioural therapy, interpersonal therapy, and other psychotherapeutic treatments. There are also creative, experiential, and somatic therapies, alongside many other kinds of treatment. Many young people benefit from a combination of different types of treatment in a whole-person approach that addresses their multiple needs.

The Wave – Mental Health Treatment Tailored to the Specific Needs of Young People

The Wave Clinic offers transformative recovery programs for young people, supporting them to plan and build fulfilling futures. Our whole-person approach combines exceptional clinical care with education, community responsibility, and a gap year experience, offering teenagers and adolescents the chance to reconnect with themselves and their love of life.

Our expert team draws on teenage and adolescent mental health specialists from around the world with unequalled experience in care and recovery. We believe that no one should be overlooked or left behind because of their mental health, providing inclusive care for all young people.

If you have any questions or would like to start the admissions process, reach out to us today. We’re here to help.

Fiona - The Wave Clinic

Fiona Yassin is the founder and clinical director at The Wave Clinic. She is a U.K. and International registered Psychotherapist and Accredited Clinical Supervisor (U.K. and UNCG).

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