If you or someone you love experiences intense mood changes, impulsive behavior, or emotional ups and downs, you may wonder whether you’re dealing with borderline personality disorder (BPD) or bipolar disorder. The two conditions can look similar, but they are different mental health conditions with different patterns and treatment approaches.
Knowing how to distinguish the two can give you a sense of how to move forward, but remember that you aren’t alone in figuring out a diagnosis. A thorough evaluation can identify what you’re experiencing and what kind of support may be most helpful.
What You’ll Learn
- What are the key differences between borderline personality disorder and bipolar disorder?
- How do BPD and bipolar disorder affect mood, relationships, and behavior?
- How can you tell the difference between BPD emotional dysregulation and bipolar mood swings?
- Why can BPD and bipolar disorder be difficult to distinguish or misdiagnosed?
- What treatments and support are available for BPD and bipolar disorder?
Quick Read
Borderline personality disorder (BPD) and bipolar disorder (bipolar I disorder and bipolar II disorder) can share symptoms like intense emotions, impulsivity, irritability, and mood changes, but they are different mental health disorders.
BPD typically involves rapid emotional shifts, relationship difficulties, fear of abandonment, and an unstable sense of self, while bipolar disorder involves distinct episodes of depression, mania, or hypomania that generally last days or weeks.
Because symptoms can overlap or occur together, a thorough evaluation is important. Treatment also differs, with psychotherapy such as DBT playing a central role in BPD treatment and medication typically being a key part of bipolar disorder treatment.
Borderline Personality Disorder vs. Bipolar Disorder
The simplest way to think about the difference between BPD and bipolar disorder is in terms of patterns over time.
- Borderline personality disorder involves ongoing difficulties with emotional regulation, relationships, self-image, and reactions to perceived rejection or abandonment. Emotions can shift quickly, sometimes within hours.
- Bipolar disorder involves distinct episodes of depression, mania, or hypomania. These episodes typically last days or weeks and can occur even without an obvious external trigger.
- BPD is primarily treated with psychotherapy, while bipolar disorder typically requires medication as a central part of treatment, often combined with psychotherapy.
There is also significant overlap between the two. Both can involve impulsivity, irritability, emotional distress, self-harm, and suicidal thoughts or behaviors. That’s one reason an experienced clinician needs to look at the person’s whole history, including trauma, relationships, and childhood experiences, rather than focusing on one symptom or one difficult period.
What Is Borderline Personality Disorder?
Borderline personality disorder is a mental health condition characterized by persistent patterns of emotional instability, relationship difficulties, and an unstable sense of self. BPD is estimated to impact up to 6% of adults, but symptoms often emerge by adolescence or early adulthood.
A central feature of BPD is a deep fear of abandonment or rejection. Someone with BPD may go to great lengths to prevent real or perceived loss or abandonment, such as seeking frequent reassurance, becoming highly attached to others, or rejecting others to avoid the pain of being rejected. This sensitivity often stems from a deeply rooted belief that they are unworthy of love or that the people they care about will eventually leave.
This fear contributes to severe black-and-white thinking in relationships and everyday life. For example, someone with borderline personality disorder may idealize a person, seeing them as wonderful or even perfect, and then suddenly devalue, resent, or fear that same person. These emotional swings can happen within an hour or two. This pattern of intense instability leaves little room for any middle ground and is known as splitting.
Common Signs of Borderline Personality Disorder
Common indicators of BPD include:
- Strong underlying fears of abandonment or rejection
- Extreme emotions and moods that change rapidly
- Unstable relationships
- An unstable and negative sense of identity or self-image
- Impulsivity
- Risky and unsafe behaviors
- Chronic feelings of emptiness
- Intense or explosive anger
- Self-harm or suicidal behaviors
- Dissociation or feeling disconnected from yourself, particularly during periods of stress
Borderline Personality Disorder and Comorbid Conditions
Borderline personality disorder can severely impact relationships, career, and everyday life. Its development and severity can be shaped by several factors, including family history and environmental factors. Some of the most common comorbid conditions are anxiety, mood disorders, other personality disorders, and substance use disorders.
Substance Use
Emotional neglect can increase the risk of borderline personality disorder, and BPD itself can create additional relationship and daily living challenges. As a result, many people turn to coping mechanisms like alcohol to numb the difficult feelings. In fact, 50% of people with BPD have a co-occurring substance use disorder.
Eating Disorders
Around 30% of patients with BPD also develop eating disorders. This may be because a vast majority of people diagnosed with BPD are girls and women, many of whom attempt to control their relationship with food when they feel out of control in other areas of their life.
Suicidality
Among the most sobering statistics about BPD are suicide rates. The rate of suicide is 50 times higher in BPD populations than in the general population, and up to 85% of people with borderline personality disorder attempt suicide at least once in their lives. Additionally, around 20% of people seeking emergency care at psychiatric hospitals are estimated to have borderline personality disorder.
Borderline Personality Disorder Treatment
The statistics and experiences of BPD are concerning, to say the least. People with this condition tend to need serious mental health support. Luckily, treatment can really help.
Dialectical Behavior Therapy (DBT) is one of the best-known evidence-based treatments for BPD. DBT helps people develop practical skills to manage intense emotions, better regulate their own emotions, navigate relationships, tolerate distress, and respond to difficult situations without making things worse.
Another helpful approach is mentalization-based therapy. This teaches people with BPD how to imagine better and understand another person’s feelings so they can respond more appropriately to the people in their lives.
What Is Bipolar Disorder?
Bipolar disorder is a mood disorder involving recurring episodes of depression and mania or hypomania. Around 4.4% of U.S. adults are estimated to experience it in their lifetimes.
Bipolar disorder includes several forms:
- Bipolar I disorder: Involves at least one manic episode, which may be severe enough to require hospitalization. Depressive episodes are also common.
- Bipolar II disorder: Involves episodes of hypomania and major depression but not full mania
- Cyclothymic disorder: Involves longer-term fluctuations in mood that don’t meet the full criteria for manic, hypomanic, or depressive episodes
Bipolar Disorder Symptoms and Signs
Bipolar disorder is characterized by distinct and alternating periods of extreme shifts between depression and mania or hypomania.
During mania or hypomania, people with bipolar disorder may experience unusually high, euphoric, or irritable mood, increased energy and activity, decreased sleep, racing thoughts, rapid speech, impulsive decisions, risky behavior, and inflated self-esteem. Hypomanic episodes are a milder form of mania and can involve many of the same symptoms, but with less severe impairment. Severe mania can also involve psychosis and breaks in reality.
A major depressive episode can include depressive symptoms such as persistent sadness, loss of interest, fatigue, changes in sleep or appetite, difficulty concentrating, feelings of worthlessness, and thoughts of death or suicide.
Mania associated with bipolar disorder can initiate bouts of risky behavior, impulsivity, and unstable moods, but unlike BPD, those experiences tend to occur in more predictable cycles.
Bipolar Disorder and Comorbid Conditions
Bipolar often coexists alongside other mental health conditions. People with bipolar disorder are likely to have higher co-occurrences of substance use, ADHD, depression, and anxiety. Interestingly, they also tend to have medical comorbidities, including asthma, obesity, high blood pressure, osteoarthritis, and thyroid disease.
While manic episodes can make people feel like they’re on top of the world, depressive episodes can be incredibly destabilizing. Intense depressive episodes can trigger suicidal behavior, and suicide attempts among bipolar patients are estimated to be up to 30 times higher than in the general population.
How Is Bipolar Disorder Treated?
Bipolar disorder is caused primarily by brain chemistry and genetics, and is generally treated well with medications such as mood stabilizers or certain antipsychotic medications. Psychoeducation and therapy are also supportive treatment approaches to help people navigate life with mania and depression.
Bipolar vs. Borderline Personality Disorder: Side-by-Side Comparison
| Feature | Bipolar Disorder | Borderline Personality Disorder (BPD) |
| Classification | Mood disorder | Personality disorder |
| Mood pattern | Distinct episodes of mania, hypomania, and/or depression | Ongoing emotional dysregulation with rapid mood shifts |
| Duration | Episodes generally last days to weeks or longer | Mood can shift within hours or days |
| Triggers | Episodes may occur without an immediate external trigger | Often connected to interpersonal stress, rejection, or perceived abandonment |
| Age of onset | Often begins in adolescence or young adulthood | Patterns often emerge by adolescence or early adulthood |
| Self-image | Often relatively stable outside of mood episodes | Frequently unstable or changing |
| Relationships | May become disrupted during mood episodes | Relationship instability is often a central, ongoing pattern |
| Primary treatment | Medication, often combined with therapy | Psychotherapy, particularly structured approaches such as DBT |
| Impulsivity | Often increases during mania or hypomania | Often occurs as part of emotional distress or interpersonal conflict |
| Self-harm/suicide risk | Elevated, particularly during depressive or mixed episodes | Elevated, with recurrent self-harm common in some individuals |
How Do You Distinguish BPD Emotional Dysregulation From Bipolar Mood Swings?
One of the biggest differences between BPD vs. bipolar is how mood symptoms develop and how long they last.
With BPD, emotional changes tend to be rapid and reactive. A person might feel fine in the morning, become intensely angry from a seemingly tiny trigger in the afternoon, and feel devastated or afraid of being abandoned that evening. The emotions are extremely intense, and they often correspond to what is happening in the person’s relationships or environment.
With bipolar disorder, mood changes are more likely to occur as distinct episodes. A manic, hypomanic, or depressive episode can continue for days or weeks. Episodes don’t always have an obvious connection to something happening in the person’s relationships or environment, although things like stress or seasonal changes can certainly be triggers.
Whether someone is getting enough sleep and their energy level can also provide important clues. Someone experiencing mania or hypomania may need significantly less sleep while simultaneously feeling unusually energetic, driven, or activated. Bipolar depression can also bring prolonged changes in sleep, energy, appetite, concentration, and motivation.
These distinctions aren’t always obvious, however. Someone can have bipolar disorder and still experience intense emotional reactions to relationships, just as someone with BPD can experience periods of depression that last longer than a few hours. That’s why duration, triggers, symptoms, age of onset, family history, and patterns across a person’s lifetime all matter when making a diagnosis.
Misdiagnosis Between Borderline Personality Disorder and Bipolar Disorder in Mental Health
BPD and bipolar disorder are separate diagnoses, but since they share several symptoms, one is sometimes misdiagnosed as the other. If a clinician only sees someone during a crisis or a particularly intense period, it can be difficult to distinguish what’s underneath the behaviors or symptoms.
A careful assessment looks beyond mood and emotional regulation. Clinicians may ask about:
- How long mood changes typically last
- Whether they occur in response to interpersonal events
- Changes in sleep and energy
- Periods of mania or hypomania
- Long-term relationship patterns
- Self-image and identity
- Impulsive or self-harming behaviors
- Family mental health history
- Substance use and medical factors
Getting the Right Support for Bipolar Disorder or BPD
Whether you’re experiencing symptoms of bipolar disorder, BPD, both, or something else entirely, you don’t need to figure out how to cope by yourself. We’re here to help you.
At PrairieCare, we believe mental health care should meet people where they are. That’s why we offer multiple levels of care, comprehensive treatment approaches, and evidence-based therapies throughout Minnesota.
Our programs include clinic and outpatient services, Intensive Outpatient Programs (IOP), Partial Hospitalization Programs (PHP), residential care, and inpatient psychiatric hospitalization for people experiencing a crisis. No matter what you’re experiencing, you’ll get evidence-based, whole-person care tailored to your needs, delivered by a multidisciplinary team of mental health experts.
If you’re unsure what kind of care you need, that’s okay. Call PrairieCare at 952-826-84745 to talk through your options and take the first step toward getting support. You can also request a screening using the button below.
FAQs
Can you be diagnosed with bipolar disorder and borderline personality disorder?
- Yes. Bipolar disorder and BPD can occur together, and research suggests this overlap is clinically significant.
Why is borderline personality disorder often misdiagnosed as bipolar disorder?
- Both conditions can involve intense mood changes, impulsivity, irritability, and self-harm. Looking at the duration and triggers of mood changes, along with long-term relationship and self-image patterns, can help clinicians distinguish between them.
How can you tell the difference between BPD emotional dysregulation and bipolar mood swings?
- BPD mood shifts are often rapid and connected to interpersonal stress or perceived rejection. Bipolar mood changes typically occur as more sustained episodes of mania, hypomania, or depression that can last for days or weeks.
How do age of onset and episode duration help distinguish BPD from bipolar disorder?
- BPD patterns often become apparent during adolescence or early adulthood, while bipolar disorder commonly emerges during adolescence or young adulthood as distinct mood episodes. However, age of onset alone cannot determine a diagnosis.
Is BPD treated with medication like bipolar disorder?
- Medication is a core component of bipolar disorder treatment, and it can definitely also be used to address specific symptoms or co-occurring conditions of BPD. However, psychotherapy is the primary treatment for BPD, with DBT being one of the best-established approaches.
When should I seek professional help for mood swings?
- Consider seeking an evaluation when mood changes, impulsivity, depression, relationship difficulties, or other symptoms are interfering with daily life or causing significant distress. A professional can help determine what’s happening and recommend the appropriate level of care.