Navigating Diagnostic Challenges (1)

Navigating Diagnostic Challenges: Borderline Personality Disorder vs Bipolar Disorder

Borderline personality disorder (BPD) and bipolar disorder (BD) can be easily confused with one another. Not only do BPD and BD have nearly identical abbreviations, they also have very similar symptoms. Knowing how to distinguish borderline personality disorder vs bipolar disorder can help you avoid misdiagnosis, ineffective interventions, and less-than-desirable treatment outcomes.

Similarities: Borderline Personality Disorder and Bipolar Disorder

Initial phone calls, clinical intakes, and assessments for those with borderline personality disorder and bipolar disorder can feel strikingly similar. When experiencing this, you’ll notice that both BPD and BD can (but don’t always) include nearly identical symptoms of: [1]

  • Impulsive behaviors
  • Mood instability/swings
  • Significant shifts in self-esteem
  • Suicidal behaviors or gestures
  • Dissociation or paranoia

Let’s break down some details about each diagnosis (don’t worry - we’ll do this in bite-sized pieces), and then we’ll dive into the differentials.

Borderline Personality Disorder Symptoms

The Diagnostic And Statistical Manual Of Mental Disorders (DSM-5-TR), defines borderline personality disorder as “a pattern of instability in interpersonal relationships, self-image, and affects, and marked impulsivity. To justify a BPD diagnosis, symptoms must begin by early adulthood and be present in a variety of contexts, as indicated by five (or more) of the following: [4]

  1.  Frantic efforts to avoid real or imagined abandonment.
  2.  A pattern of unstable and intense interpersonal relationships.
  3.  Identity disturbance: unstable self-image or sense of self.
  4.  Impulsivity that is potentially self-damaging (substance abuse, binge eating, spending).
  5.  Affective instability due to reactivity of mood (typically for only a few hours)
  6.  Chronic feelings of emptiness.
  7.  Inappropriate, intense anger or difficulty controlling anger.
  8.  Transient, stress-related paranoid ideation or severe dissociative symptoms.

*Note: The DSM-5 includes an Alternative Model for Personality Disorders to address limitations of its traditional categorical definition.[4]

Borderline Personality Disorder Risk Factors and Triggers

Research tells us that a combination of genetic factors and adverse childhood experiences create a significant risk to the development of BPD. [3]  It is five times more likely for someone with first-degree biological relatives to develop BPD as compared to the general population.[4] Family history of borderline personality disorder, disorganized attachment styles, and adversity (both in early life and young adulthood) are all associated with the possible development of BPD. [3]

It's believed that those with BPD usually have heightened rejection sensitivity, insecure attachment styles, temperamental sensitivity to psychological pain for interpersonal conflict, difficulty regulating mood, and a chronically unstable self-image. Due to this, common triggers for BPD include:

  • Rejection and abandonment
  • Disappointment in others
  • Interpersonal offenses and betrayals
  • Being alone
  • Boredom or disconnection to preferred stimulus
  • Identity threat (having one’s self-concept threatened)

Revictimization within romantic relationships, bully-victim dynamics with friends, coworkers, etc., and other interpersonal concerns lead to an increased distrust of others and social isolation. This can begin a vicious cycle for those who develop BPD.

Bipolar Disorder Symptoms

Bipolar disorder causes significant shifts in an individual’s mood, energy, activity levels, and concentration.[9]  These shifts, lasting from days to weeks, can cause impairment or disruption to daily activities like self-care (showering, laundry, etc.), school, work, and/or caretaking responsibilities.[10]

There are three different kinds of bipolar disorders, and additional related disorders.[4] We’ll focus on the bipolar disorders, which include:

  • Bipolar 1 disorder: Manic or mixed feature episode with or without psychosis and/or major depression
  • Bipolar 2 disorder: Hypomanic episode with major depression. No history of mania. Might have a history of hypomania
  • Cyclothymic disorder: Hypomanic and depressive symptoms that do not meet bipolar II disorder criteria. No major depressive episodes. Occurring over two years, with no more than two months free of symptoms.

Manic, hypomanic, and major depressive episodes can show up in these ways: [2]

*1 week *4 consecutive days *2 weeks
Persistent elevated, expansive, or irritable mood Persistent elevated, expansive, or irritable mood Depressed mood most of the day, nearly every day
Increased activity or energy Increased activity or energy Markedly diminished interest or pleasure in all, or almost all activities
Inflated self-esteem or grandiosity Inflated self-esteem or grandiosity Significant weight loss or gain; decrease/increase in appetite
Decreased need for sleep Decreased need for sleep Insomnia or hypersomnia; fatigue or loss of energy
More talkative than usual More talkative than usual Noticeable increase or decrease in psychomotor functioning
Flight of ideas/racing thoughts Flight of ideas/racing thoughts Feelings of worthlessness or excessive/inappropriate guilt
Increase in goal-directed activity or psychomotor agitation Increase in goal-directed activity or psychomotor agitation Diminished ability to think/concentrate
Excessive involvement in activities that have a high potential for painful consequences Excessive involvement in activities that have a high potential for painful consequences Recurrent thoughts of death, recurrent SI (with or without plan or with or without attempt)
Severe | marked impairment | possible hospitalization | possible psychotic features Change in functioning observable by others | uncharacteristic when not symptomatic Clinically significant distress or impairment | change from previous functioning

Bipolar Disorder Risk Factors and Triggers

Most mental health professionals believe that various factors contribute to a person’s risk of developing bipolar disorder. However, many studies demonstrate that a strong influence is genetic predisposition.[2]

Research shows us that individuals who have an immediate family member with bipolar disorder are at an increased likelihood of developing BD. In fact, estimates of heritability are at around 90% in some twin studies.[4] There are many different genes with different genetic origins that contribute to the development of bipolar disorder – so, we cannot point to just one. [9]

Genetic predisposition combined with stress and the person’s environment is likely the primary risk factor for the development of bipolar disorder.[4] Environmental triggers for BD can include: [2] [10]

  • Stress
  • Shift work
  • Travel across time zones
  • Seasonal light changes
  • Sleep disruption
  • Hormonal fluctuations
  • Drugs and alcohol use

Similarly to borderline personality disorder, adversity is a known trigger.[4] Trauma, family conflict, and negative life events can all contribute to both the development, and maintenance of BD.[1]

FREE DOWNLOAD: Use this diagnostic resource to help you differentiate between Borderline Personality Disorder and Bipolar Disorder.

Bipolar Disorder or Borderline Personality Disorder Tool

Differentiating Between Borderline Personality Disorder vs Bipolar Disorder

Applying evidenced-based screening tools, developing your knowledge of important diagnostic themes, asking the right assessment questions, and involving your clients’ support persons (when possible) will collectively help you differentiate between borderline personality disorder vs bipolar disorder.

The Patient Health Questionnaire, Mood Disorder Questionnaire (MDQ) and McLean Screening Instrument for Borderline Personality Disorder (MSI) are evidenced-based tools that can aid you in the discernment of BPD vs BD. [2] [11] ICANotes users can access all of these tools (and more) in their ICANotes Behavioral Health EHR, which includes over 75 different electronic rating scales and assessments.

While completing initial client intakes or assessments, keep these three diagnostic themes in mind:

  • Episodic vs. Pervasive: A key differentiator between the two disorders is the episodic nature of bipolar disorder: meaning symptoms occur occasionally and at irregular intervals.[2] Individuals with bipolar disorder show a noticeable increase in symptoms that are above or below their baseline. [2] These episodes are clearly defined with a starting, and stopping point. In contrast, borderline personality disorder is more pervasive – meaning symptoms are consistent over a long period of time. [3]
  • Age of Onset: Age of onset can also help distinguish between the two. While bipolar disorder can develop at any point in a person’s life (with special precautions given when diagnosing a child, or older adult), borderline personality disorder always emerges by early adulthood (sometimes as early as 12 or 13).[4]
  • Relation to Baseline: Gathering collateral from friends/family of your client (with approval, of course) can also help you differentiate. Because bipolar disorder is episodic, and can occur at any point in a person’s life, family and friends are more likely to notice or describe their loved one’s symptoms as “out of character.”[6] With borderline personality disorder emerging before early adulthood and being pervasive, friends and family of those living with BPD may struggle to differentiate the disorder from their loved one’s “typical” or normal day-to-day. [6]

The ICANotes Behavioral Health EHR will help you simplify your intake sessions by having screening tools and behavioral health assessments organized, and easily accessible in one place. On top of that, any intake tools you use while working with your client will be integrated into their individual mental health chart, ensuring all your client’s records are safely stored, and available to seamlessly integrate into their treatment plan.

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Treatment Differences: Borderline Personality Disorder vs Bipolar Disorder

Getting the right diagnosis is often the first step to getting the right treatment. This is true for many mental health disorders, but especially borderline personality disorder and bipolar disorder. Let’s take a look at the differences in effective treatment for BD vs BPD.

Bipolar Disorder Treatment: Medication is the cornerstone to effective treatment for bipolar disorder.[9] Psychotherapy can help your clients learn about bipolar disorder, develop coping skills, and adhere to medications. However, the absolute best practice to combine psychotherapy with medications.[10] Early detection and treatment of bipolar disorder can decrease a person’s risk of relapse and double the rate of response to medications. [2]

Borderline Personality Disorder Treatment: Psychotherapy is the cornerstone to effective treatment for borderline personality disorder.[3] Dialectical behavior therapy, mentalization‐based therapy, transference‐focused therapy, and schema therapy are all evidenced-based therapy approaches for the treatment of BPD. According to various studies, all of these therapy approaches result in similar outcomes.[5]

Medications are not typically used to treat borderline personality disorder, as there are unfortunately no clear benefits. Your client’s physician may prescribe medications to treat a specific symptom of BPD, or to treat a co-occuring disorder like depression or anxiety.

Instant Webinar

Access this insightful webinar where we navigate the complexities of distinguishing between Borderline Personality Disorder (BPD) and Bipolar Disorder (BD). With their overlapping symptoms and potential for misdiagnosis, understanding the nuances is crucial for accurate assessment and effective treatment.

What You'll Learn

  • Recognize the key similarities between BPD and BD to understand potential misdiagnoses.
  • Understand the significance of accurate diagnosis, especially when distinguishing between BPD and BD.
  • Discover essential diagnostic themes to help differentiate between BPD and BD.
  • Gain foundational knowledge of treatment strategies for both BPD and BD.
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Documenting Progress

Documenting your clients’ responses to the treatment approaches listed above is key to confirming whether or not you’re on the right diagnosis and/or treatment track. With the right documentation tools from ICANotes, you can create unique progress notes quickly and effectively after every session – ensuring you’re prepared, organized and ready to best help your client at their next session.

Outside of helping you create progress notes, ICANotes behavioral health software makes it easy to improve compliance and bill more effectively, ensuring you get to spend focused, ample, and productive time with your patients. Schedule a demo today or start your free trial to see how ICANotes can support you in providing the most effective, high quality care possible.

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About the Author

KBendel Headshot

Katie Bendel - LCSW

Katie Bendel (she/her) is a therapist, writer, public speaker, and community connector. In her 10+ years of experience working in the mental health field, she has come to believe this:

As people, we thrive in – 1) authentic, empathetic, and vulnerable relationships with others 2) sense of safety – physically, mentally/emotionally, socially, etc. 3) connection to our values – what matters most to us. As a Licensed Clinical Social Worker (LCSW), Katie has dedicated her life to helping people access
that beautiful triad.

Katie has walked alongside thousands of individuals on various journeys, including those seeking eating disorder or substance abuse recovery, and those learning to cope with mood, anxiety, and trauma-related disorders. As part of this, she’s guided countless caregivers, family and friends who are eager to support their loved ones’ healing. Over the last decade, Katie has served in various roles such as individual therapist in the outpatient setting, clinical assessment for higher levels of care, residential program support (milieu coordination, group therapy, etc.), aftercare planning, resource development, community education (writing, speaking, etc.), and more.

Katie currently divides her time among various professional areas and settings. Her primary attention is with a national mental health treatment facility where she assists in resource development, community education, and facilitating peer-to-peer connection. In addition to this, Katie is a mental health therapist in group practice.


  1. American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.).
  2. Marzani, G., & Price Neff, A. (2021). Bipolar Disorders: Evaluation and Treatment. American family physician, 103(4), 227–239.
  3. Leichsenring, F., Fonagy, P., Heim, N., Kernberg, O. F., Leweke, F., Luyten, P., Salzer, S., Spitzer, C., & Steinert, C. (2024). Borderline personality disorder: a comprehensive review of diagnosis and clinical presentation, etiology, treatment, and current controversies. World psychiatry: official journal of the World Psychiatric Association (WPA), 23(1), 4–25.
  4. American Psychiatric Association. (2022). Diagnostic and statistical manual of mental disorders (5th ed., text rev.).
  5. Woodbridge, J., Townsend, M., Reis, S., Singh, S., & Grenyer, B. F. (2022). Non-response to psychotherapy for borderline personality disorder: A systematic review. The Australian and New Zealand journal of psychiatry, 56(7), 771–787.
  6. Howard, G., & Washington, N. (hosts). Inside Bipolar . PsychCentral.
  7. Choi-Kain, L. W., Sahin, Z., & Traynor, J. (2022). Borderline Personality Disorder: Updates in a Postpandemic World. Focus (American Psychiatric Publishing), 20(4), 337–352.
  8. Miskewicz, K., Fleeson, W., Arnold, E. M., Law, M. K., Mneimne, M., & Furr, R. M. (2015). A Contingency-Oriented Approach to Understanding Borderline Personality Disorder: Situational Triggers and Symptoms. Journal of personality disorders, 29(4), 486–502.
  9. National Institute of Mental Health. (2024, February). Bipolar Disorder. U.S. Department of Health and Human Services, National Institutes of Health.
  10. American Psychiatric Association (2024, April). What are Bipolar Disorders?.
  11. Palmer, B. A., Pahwa, M., Geske, J. R., Kung, S., Nassan, M., Schak, K. M., Alarcon, R. D., Frye, M. A., & Singh, B. (2021). Self-report screening instruments differentiate bipolar disorder and borderline personality disorder. Brain and behavior, 11(7), e02201.