Borderline Personality Disorder vs. Bipolar Disorder: Key Differences Explained

July 10, 2025

Authored by: Jayme Wium, Writer

Edited by: Emma Loker, B.S

Our moods naturally change as a response to stressful situations. However, for some people, mood shifts can become extreme and may be a sign of more serious conditions like bipolar disorder (BD) or borderline personality disorder (BPD).

It’s not unusual to see BPD vs bipolar symptoms that look similar to each other. For instance, some similarities between bipolar and BPD include being impulsive or having major mood swings. Such similarities can create an overlap that makes it easy to confuse and challenging to differentiate the two conditions.

You may be wondering whether the highs and lows you experience are BPD and bipolar related – or whether you may have a misdiagnosis as a result of overlapping symptoms. Knowing the difference between BPD and bipolar disorder is critical for ensuring an accurate diagnosis and meaningful recovery.

Unfortunately, there’s no simple BPD or bipolar test that can easily define one condition from another – clarity usually takes time and expertise. However, exploring the difference between BPD and bipolar can help you make sense of symptoms and guide you toward the right options for treatment. A mental health professional is always at hand during this process.

This guide can also help by exploring:

How BPD vs bipolar symptoms compare in real life
Why mood swings in BPD vs bipolar differ
What to expect from the BPD vs bipolar diagnosis process
The best types of therapy for BPD vs bipolar disorder
Actions you can take when you get a misdiagnosis of BPD as bipolar

Are BPD and Bipolar Disorder Related?

Are BPD and bipolar disorder related, and how do they differ? While both borderline personality disorder and bipolar disorder have some similarities, they also have distinctive core differences and varying clinical diagnostic criteria.

To begin with, the Diagnostic and Statistical Manual of Mental Disorders (DSM) lists BPD under “Personality Disorders.”¹ This is because it’s characterized by long-standing patterns of instability and impulsive behavior that affect relationships and functioning. For example, in BPD, relationship behaviors can alternate between extremes of idealization and devaluation. Self-image and esteem can also be unstable in BPD.

In contrast, bipolar disorder appears under the “Bipolar and Related Disorders” section in the DSM. It’s a mood disorder characterized by clear episodes of mania or hypomania that alternate with depression. Bipolar disorder can be difficult to recognize and is sometimes misdiagnosed initially. For instance, studies show that patients are often incorrectly diagnosed until around 6 to 10 years after first contact with a healthcare provider.²

Episodes in bipolar disorder may or may not be triggered by life events and tend to be more episodic than the ongoing emotional fluctuations seen in BPD.

Understanding this core distinction, which involves trait-based instability in BPD versus episode-based dysregulation in bipolar, can help untangle the confusion when wondering if the two conditions are related.

BPD vs Bipolar Symptoms

Thinking of BPD vs bipolar symptoms as a comparison between emotional instability vs mood episodes can make the conditions easier to understand.

Emotional shifts or instability in BPD are usually fast, situational, and reactive, and are typically triggered by interpersonal stress. This instability is often linked to trauma or insecure attachment patterns. In comparison, mood episodes in bipolar disorder change more slowly, and life events don’t have to be a catalyst.

Let’s break these symptoms down further in the following sections.

Symptoms of Borderline Personality Disorder

At least five of the nine formal borderline personality disorder symptoms are required to establish a diagnosis.³ These include:

A pattern of intense and unstable interpersonal relationships
Frantic efforts to avoid real or imagined abandonment
Disturbances in identity, marked by an unstable sense of self
Self-damaging impulsivity, such as spending, unsafe sex, binge eating, using substances, or reckless driving
Suicidal or self-harming behaviors or threats
Instability, like anxiety or irritability, that only lasts a few hours and rarely more than a few days
Chronic feelings of emptiness
Difficulty controlling anger or inappropriate, intense anger. For example, engaging in frequent physical fights or having regular temper tantrums
Severe dissociative symptoms or stress-related and short-lived paranoid thoughts

Symptoms of Bipolar Disorder

When it comes to bipolar disorder, symptoms can vary based on whether it’s a bipolar I or bipolar II disorder.⁴ Diagnosing bipolar I requires meeting the criteria for manic episodes. These are distinct periods of persistently elevated or irritable mood with increased activity or energy. Manic episodes last for at least seven consecutive days and sometimes require hospitalization.

For a manic episode qualification, three of the following symptoms must be present, or at least four if the mood is irritable:

High self-esteem or grandiosity
Being more talkative than usual or having a compulsion to keep talking
A reduced need for sleep
Racing thoughts or flights of ideas
Feeling easily distracted
Increased goal-directed activities or frequently engaging in actions that don’t have a specific purpose
Engaging in high-consequence activities like sexual indiscretions, buying sprees, or bad investments

For a bipolar II diagnosis, both a major depressive episode and a current or previous hypomanic episode must be present. Hypomanic episodes refer to persistently irritable or elevated mood periods with increased energy or activity lasting at least four consecutive days.

A minimum of five or more of the following major depressive episode symptoms must be present daily (or nearly every day) for a consecutive 2-week period:

Feeling depressed the entire day
Significant weight gain or loss when not dieting
An increase or decrease in appetite
Being unable to feel pleasure for most of the day
Excessive sleepiness or lack of sleep
Loss of energy or fatigue
Excessive and inappropriate feelings of guilt or worthlessness
Indecisiveness or decreased concentration
Recurrent suicidal thoughts or ideations without a specific plan

How Professionals Diagnose Between BPD vs Bipolar Disorder

Telling the clinical difference between BPD and BD has always been a challenge, as misdiagnoses of BPD as bipolar occur in around 40% of cases.5 Comorbidity between the two also makes things even more challenging, with research showing that one in five people with either BPD or bipolar disorder has the other condition.^6,8

For this reason, clinicians use more than just a checklist to discern between BPD and bipolar disorders. The diagnostic process can’t be rushed, and information from loved ones who can speak about behavior patterns across different settings is often gathered. With a detailed medical and personal history and in-depth understanding of the differences between BPD and bipolar disorder, professionals are more capable of accurately diagnosing and delivering appropriate treatment.⁷

Psychiatric evaluations are also usually conducted in the BPD vs bipolar diagnosis process. For bipolar disorder, these evaluations look for signs of manic episodes, with durations ranging from four days to seven days. Behavioral patterns like psychotic features, risky decisions, or a decreased need for sleep usually determine the diagnosis. In contrast, when it comes to BPD, evaluations tend to focus on long-term emotional patterns, identity instability, and how someone navigates relationships.

As a note, many people search for a BPD or bipolar test, hoping for a clear answer to their questions. While self-assessments exist, they should never replace a clinical diagnosis. However, they can help people better understand their experiences and how to describe them before seeking help.

One helpful tool is a BPD vs bipolar disorder chart that outlines:

Feature	BPD	Bipolar Disorder
Mood duration:	Minutes to hours	Days to weeks
Triggers:	Relational	Often internal or cyclic
Energy changes:	No clear change	High or low energy states
Self-identity:	Shifts frequently	Usually intact between episodes
Treatment:	Psychotherapy	Medication + therapy

Can You Have Both BPD and BD?

As previously mentioned, yes, it’s possible to have both BPD and bipolar disorder. Plus, the rates of comorbidity can differ depending on whether someone has bipolar I or II disorder.

Studies showed that the rates of BPD comorbidity in patients with bipolar I disorder were approximately 10%. In comparison, BPD was present in 16% of patients with bipolar II disorder.⁹ Interestingly, a family history of bipolar disorder or BPD did not influence the existence of both conditions.

When building treatment plans for patients with both conditions, professionals should carefully consider the traits and symptoms of both. For example, dialectical behavior therapy (DBT) may be effective for managing BPD stress, while the patient may also need mood stabilizers for bipolar disorder.

To make the point again, accurate diagnosis is vital. If comorbidity isn’t recognized, patients may get medications that only address one condition while the other might go untreated for extended periods. As a result, symptoms may worsen, and distress could increase. Placing trust in reputable clinicians is key in this process.

Medication and Therapy Approaches

Treatment approaches for bipolar disorder and BPD differ significantly, as the following sections demonstrate.

BPD Treatment:

One of the most effective interventions used in treating BPD is dialectical behavior therapy (DBT). This is because DBT involves teaching emotional regulation, distress tolerance skills, mindfulness, and ways to maintain positive relationships. Additionally, most studies show that both standard and short-term DBT can significantly improve general psychopathology, self-harm, depressive symptoms, and suicidal thoughts in people with BPD.¹⁰

Other effective BPD treatment approaches include:

Schema therapy: Useful in helping change long-held beliefs
Cognitive behavioral therapy: CBT teaches ways to spot and challenge thoughts that fuel shame or anger
Mentalization therapy: Helps in understanding emotions in context
Trauma-focused therapies: Suitable when childhood trauma or PTSD are present

Medications alone have not been found effective in resolving BPD. However, some medications can help alleviate anxiety or depression symptoms.

Treatment for Bipolar Disorder:

The primary routes for treating bipolar disorder include:

Psychotropic drugs
Neurostimulation therapies
Psycho-social counselling
Lifestyle modifications

Studies show that psychotropic drugs remain the foundation for any treatment plan and have been researched extensively.¹¹Common options include:

Antidepressants (ADs)
Mood stabilizers (MSs)
Benzodiazepines (BZDs)
Antipsychotics (APs)

Alongside meds, therapy plays an important supportive role in managing bipolar symptoms, including:

CBT for reframing thought patterns during depressive episodes
Interpersonal and Social Rhythm Therapy (IPSRT) for establishing mood stabilizing routines
Family-focused treatment to help reduce conflict and increase support at home

So when comparing therapy for BPD vs bipolar disorder, the difference is clear: BPD typically requires deep psychological work, while bipolar disorder demands consistent biological balancing.

Reach Out to Mission Connection for Help That Fits

If you’ve been wondering whether your symptoms point to BPD, bipolar disorder, or something else entirely, consulting with a mental health professional is advised. Navigating mental illness with mood changes can be overwhelming, especially when the distinctions between conditions are nuanced.

Having access to a place where your care fits your experience matters. Whether you’re seeking therapy, exploring diagnosis, or just starting to learn the language around your emotions, you deserve support that sees your full story – not just your symptoms.

At Mission Connection, we specialize in helping people find clarity. We understand the complexity of emotional instability vs mood episodes and know that healing starts with being heard. Contact our team if you need guidance, support, or a place to begin.

FAQs About Bipolar vs. BPD

How to Diagnose BPD vs Bipolar

There is no shortcut to diagnose either condition. Diagnosis requires multiple sessions, clinical interviews, and sometimes input from family or partners. Keeping a mood journal can help track patterns that clarify the picture.

What Are the Similarities Between Bipolar and BPD?

Both conditions can involve intense emotions, impulsivity, and suicidal thoughts. However, BPD symptoms are often tied to interpersonal stress and instability in self-image, while bipolar symptoms occur in cycles.

Why Does Misdiagnosis of BPD as Bipolar Happen?

Because surface-level symptoms like rapid mood shifts can appear similar, providers may initially mislabel BPD as bipolar if they fail to dig into the context and timeline of emotional changes.

References

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