What Is the Difference Between Bipolar Disorder and Borderline Personality Disorder?


Bipolar disorder and borderline personality disorder (BPD) are mental health disorders associated with intense mood swings. Both disorders share many similarities, such as impulsive behavior, intense emotions, and suicidal thoughts. While these disorders have many overlapping symptoms, they are each categorized differently. While bipolar disorder is considered a mood disorder, borderline personality disorder is a personality disorder. Each disorder needs a proper diagnosis and treatment to alleviate symptoms, tailored uniquely towards an individual. Before we address the differences, let’s take a look at what each mental health disorder entails. 

What Is Bipolar Disorder?

Bipolar disorder is a mental health disorder that causes dramatic shifts in an individual’s mood, energy, and thought patterns. Individuals with this diagnosis experience extremely high and extremely low moods otherwise referred to as mania and depression. Symptoms of bipolar disorder may include psychotic symptoms such as hallucinations or delusions during a period of mania alongside depressions. Individuals diagnosed with bipolar Ⅱ disorder experience hypomania instead of mania, characterized by less intense symptoms typically associated with mania. 

To be diagnosed, a person must have experienced at least one episode of mania or hypomania. Mania can be unpredictable, as mood can be elevated or irritated, and behavior and judgment are impaired. During periods of mania, impulsivity is increased, fostering potential reckless decision-making as well. 

Depression is another symptom of bipolar disorder. These lows are often so debilitating that an individual may be unable to get out of bed. Symptoms of depression can obstruct an individual’s ability to function, which must be present for at least two weeks for an accurate diagnosis. Gene and other chemical imbalances are linked to the development of bipolar disorder. 

There are four types of bipolar disorder. Each of the four types differs in duration and severity of abnormal mood levels. The four types of bipolar disorder include:

  • Bipolar Ⅰ
  • Bipolar Ⅱ
  • Cyclothymic disorder
  • Other specified and unspecified bipolar and related disorders

What Is Borderline Personality Disorder?

Borderline personality disorder (BPD) is characterized by difficulties in emotion regulation. Individuals with a diagnosis of BPD feel emotions intensely and for long durations, which means it is harder for them to stabilize emotions after a triggering experience. This may lead to impulsivity, low self-esteem, hot-and-cold relationships, and intense emotional responses to adversity.  

Some key symptoms of BPD may include: 

  • Unstable personal relationships
  • Distorted or unstable self-image
  • Periods of intense depressed mood, irritability, or anxiety lasting hours to days
  • Impulsive behaviors such as misuse of substances
  • Chronic feelings of emptiness
  • Self-harming behavior
  • Inappropriate or uncontrollable anger followed by shame or guilt
  • Dissociation from oneself 

Symptoms are usually triggered by a conflict with another person or situation. A traumatic event can also increase the severity of symptoms present. An individual with BPD typically fears abandonment in relationships and may develop harmful coping mechanisms at the cause of that. Early childhood trauma and vulnerable brain chemistry make an individual more susceptible to developing BPD. 

BPD is a condition that is diagnosed by a mental health professional following comprehensive clinical interviews. A diagnosis of BPD is not based on one specific sign or symptom.

Acknowledging the Differences 

When a person has bipolar disorder, they experience episodes of mania and depression. In between an episode of either, that person demonstrates stability in mood that a person with BPD cannot. Between episodes of intense highs and intense lows, an individual with bipolar disorder may be able to function relatively well. However, with BPD, there is minimal stability in mood and relationships. There are no clear episodes of mania or depression in BPD, as the mood of the individual is inconsistent. 

Bipolar disorder is rooted in the biology of the nervous system and the brain, developing from various genetic and biological factors. On the other hand, BPD is typically caused by trauma and other psychological factors, in addition to genetic and biological factors. Mood swings of bipolar disorder are less related to external events. Mood triggers may surface during an episode of mania and depression. However, mood changes with a BPD diagnosis tend to be at the cause of an event, arising at any time. 

Bipolar disorder and BPD are often mistaken for one another, leading to misdiagnosis. Individuals with BPD are often treated for depression or bipolar disorder and vice versa when it is a much more complex problem.  Individuals with symptoms of either disorder must consider a professional opinion, such as seeking a specialist. General doctors and physicians may not be the best fit to diagnose such disorders, as these are very complex mental health conditions. 

Mood and personality disorders can be challenging to identify. However, accuracy is crucial so that treatment can be tailored to a specific diagnosis. Bipolar disorder and Borderline personality disorder (BPD) are two mental health disorders characterized by unstable mood. Bipolar disorder is characterized as a mood disorder, and BPD is characterized as a personality disorder. To receive an accurate diagnosis of bipolar disorder, an individual would have had to experience an episode of mania and hold other symptoms of mood instability. For BPD, a diagnosis is not concluded through symptoms or experience but through comprehensive clinical interviews of trauma, emotional regulation experiences, and coping mechanisms. Casa Recovery is dedicated to providing individualized treatment for all mental health and substance use-related needs. We offer multiple services and programs to ensure the best fit for all clients. For more information, call Casa Recovery today at (888) 928-2272. Healing begins with Casa Recovery.

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