Borderline Personality Disorder and Bipolar Disorder: What’s the Difference?

JUN. 12, 2017

By Ken Duckworth, M.D.


Getting the right diagnosis often isn’t easy for psychiatric conditions. In our field, we don’t yet have biologic tests that can easily define one condition from another. If your blood pressure is 140 over 90, you have hypertension or high blood pressure. In mental health, we have to rely on a description of patterns or symptoms to makes diagnoses. This model is fraught with challenges.

Without a clear biological model to work from, and given the complexity of the human brain, the field has settled upon dividing these descriptions of symptoms into syndromes. The Diagnostic and Statistical Manual of Mental Disorders (DSM) holds these symptom descriptions in order to help professionals make reliable and consistent diagnoses. This means a social worker in Detroit should make the same diagnosis as a psychiatrist in Boston and a psychologist in Santa Fe.

However, the diagnostic process is more complex than just reading symptoms in a DSM. Here are a few thoughts on what I have observed in making diagnoses:

  • Diagnosis is best viewed as a movie, not a snapshot. In a snapshot, people with different diagnoses can appear to have similar symptoms. The key is to step back and develop a view of their history and the pattern of symptoms.
  • People may present different symptoms over time, which can change their diagnosis. A person who has a depressive disorder, for example, could have a manic episode a year later. This would change that person’s diagnosis to bipolar disorder. The original diagnosis wasn’t a misdiagnosis—rather the movie changed its storyline and the diagnosis needed to change as well.
  • It’s common to have more than one diagnosis. For many people, there may not be one simple diagnosis. For example, people can have both bipolar disorder and a substance use disorder diagnoses.
  • Medical problems or medications can influence or even mimic symptoms. Hypothyroidism presents with almost all symptoms of depression for example, and steroids can add risk for mood symptoms.
  • Get informed. Patients who know their symptoms can help in the search for a diagnosis. People have brought write-ups to their appointment as they search for answers, and I have referred some people to the DSM-5 so they can evaluate their experience.

Let’s focus on the sometimes-confused conditions of Bipolar Disorder and Borderline Personality Disorder (BPD). In a snapshot, they can look similar—both can present with impulsive behavior, intense emotions and suicidal thinking. But this snapshot is not the best way to tell them apart. It’s really the movie of the symptom presentation over time that can help make the diagnosis distinct.

Classic Bipolar Disorder Type 1 is easier to differentiate from BPD than Bipolar 2. True manic symptoms (often with hallucinations) are the hallmark of Type 1 and these symptoms are not seen in the same way in BPD. Bipolar Type 2 is a more challenging diagnosis to differentiate from BPD, because the classic manic episode is absent. So, on the surface, it can appear more like BPD. Here are a few ways to help tell the difference between bipolar and BPD:

How Often Do Moods Change?

People with Bipolar Type 1 have cycles that switch from a depressive state to a manic state. Manic symptoms sometimes include flashes of deep depression within the manic episode (called rapid cycling). Between cycles, people often have periods of true symptom-free wellness. This period of wellness can last weeks, months or years depending on the person. People diagnosed with BPD typically have more persistent day-to-day emotional symptoms which can impact everyday life. BPD mood changes are more persistent, short-lived and reactive to environmental factors, like stress at work or home.

Is Sleep Normal?

Sleep changes are often an early indicator of a bipolar disorder. During a bipolar episode, a person might be awake for days and not experience fatigue or they may sleep for days. Meanwhile, sleep patterns are less commonly impacted in BPD.

Is There a Family History?

Mood disorders, like bipolar disorder and depression, run in families, but aren’t directly passed on through a single, specific gene. A family history of mood disorders increases the chances of mood disorders appearing in relatives.

Are Relationships Often Unstable?

Intense relationships often fraught with conflict are the hallmark of borderline personality disorder. People with BPD often have intense relationship histories, and many of their experiences with emotional dysregulation (intense reactions and variabilities) are in response to relationship interactions.

Is Self-Harm a Symptom?

Self-harm such as cutting one’s skin is more common in BPD and is thought to be a way to help with emotional regulation. “I’m not suicidal, I was just trying to change my feelings by cutting,” I’ve been told by individuals with BPD. In fact, 75% of individuals with BPD have cut, burned, hit or injured themselves.

Diagnosing a mental illness isn’t like diagnosing some physical illnesses—it takes a lot of observation and understanding to find the right diagnosis. If your diagnosis doesn’t feel right or isn’t clear, it’s best to talk to your clinician. Ask about your diagnosis and treatment plan and be engaged in the diagnostic process. If you and your practitioner aren’t sure, ask for a second opinion. It’s okay not to be sure, and it’s smart to keep learning.

Both BPD and bipolar have good treatment options, but they are very different options, so putting time into getting a correct diagnosis is essential. These are serious health conditions that need individualized support and care in order to optimize recovery.


Ken Duckworth is medical director at NAMI.


SEP, 26, 2018 04:30:37 AM
Great with information not able to find elsewhere

AUG, 25, 2018 01:56:46 PM

It's been a few months and not sure you will see this. If it were me, I would see if your significant other would be willing to have you come along on a visit to her therapist/psychiatrist/etc. The idea would be to gently ask if she wouldn't mind you sharing your perspective and/or concern(s) with the mental health professional. I think often times they don't get the full picture because for some strange reason most of them don't reach out to family / friends to get more information about the patient's history, behavior over time, etc. This probably has to do with privacy laws in healthcare--but honestly it is something that should be done regularly in my opinion, whenever possible and by whatever means necessary. Anyway, if she agrees to allow this, they should be willing to have you come in with her. I did this with my mom several years ago. Just be aware that this can be a slippery slope. It could make a huge change in your life and hers--for the better--but in my experience it did not work out long term, unfortunately... It's too long to explain right now, but if you'd like to reach out to me with any questions or clarifications I'm happy to try to help. Just leave me a message here, as I've subscribed to this post.

JUL, 09, 2018 08:23:06 PM
I have mental illnesses and started when I was young and my mother also was very unstable with her disorders of mental illness I was diagnosed bipolar type 1 and PTSD, Borderline Personalities, Anxiety Disorder and with Psychotic features and yes younger I was very angry and always violent and was cutting and that would turn my thinking away from hurting other's very badly to extreme and impulsive thoughts I wanted to do to them because of the hurt or trauma they caused me which the older I got I was worse and medications wasn't right and then self medicating just made it worse I was abused badly from young age as rape, emotional, mental, verbal, physical abuse from family and others out of relationships that wouldn't last because toxic and I wouldn't take abuse physically and all the trauma and hurt still keeps happening even when I thought it was ok and now my mental illness got more unstable after I was with a man I truly loved as a soulmate and he enabled me so my thinking wasn't clear throughout our time together and I was doing time for anger that led into violence and aggravated assaults and drinking and driving and finally done everything and went to get help and lots of therapy and learned how to control anger and coping skills and alcoholism was a lot of the issue not helping matters but after I got help and quit putting poison in my body and took medicine right my mind was clear and then I was seeing more clearly of the issues that were getting in my relationship and I done so much for everyone and big heart always just don't trust easy but I was in love and family I thought was happy with me and then finding out lies and secrets and just obviously things are wrong and getting worse he was a narcissistic sociopath with evil tendencies a personality disorder I never knew that it was something that is unbelievably still haunting me and with his ways of his symptoms and mine we were toxic I couldnt believe how he changed from Prince to devil and still evil and he is nice then I know it will turn bad I know him like a book now I'm scared and paranoid because he's abused me and hurt me in every way possible and turning everyone away out of my life so I have nobody at all except him and he is evil and he and I couldn't even get along because I call him out when his lying and secrets and I can read right through him he tells on himself but always turned it around and it was me who hurt him and I am emotionally and mentally abused and thinking am I that bad of a person and why did he turn on me and who is he what happened to our love I thought he was as in love with me as I still am with him and he don't have emotion or anything just scary and I left him and wanted a divorce and he stalked me and got others to turn on me and taunt me and mentally play head games and put me down and then trying to put me away and making me feel like I was losing my mind and knowing now what I'm dealing with I'm aware of my surroundings and how dangerous he is we divorced and he still won't stop and won't let me go and he don't want me to have anyone else in my life he is in control and I just wanted to say mental illnesses a lot of people don't know a lot about it or research it mostly when someone in your life has something of mental illness please research it and make sure you know how to function and cope with symptoms of some but I can't believe how far I come with already mental illness and then dealing with someone that don't care about me at all but against me and enjoys hurting me and I try to stay strong and get help so that's what I thought I wanted to share with you and aware that it's serious when you deal with mental illness.

JUL, 04, 2018 01:04:55 PM
AA has always seemed to me like viable option since there are people in similar circumstances. From what I’ve heard AA is a Christian org. If they would stop pushing god, I would get their help.

JUN, 01, 2018 09:44:17 AM
I am in love with a woman who has been treating for bipolar and in talking to her friends, she exhibits many of the characteristics of BPD. Her behavior and mood swings cause concerns for her safety. Her driving literally scares me. She is receiving treatment however I believe her current regiment is not providing the care needed. I have concerns that she might not be totally up front with her therapist, could I intervene? I care about her and want to marry her, however in the past 2 weeks Her mood swings are more intense, her behavior more erratic and she is more withdrawn. She claims her medications are not working. She has abandonment issues, I have tried to reassure her I will not abandon her and have tried to provide a loving and stable home environment.
Where do I go from here?

APR, 15, 2018 11:55:36 AM
Anne Sullivan
Just discovered you, and what a gift you are! Living with BPD and PTSD Extended. Elderly
widow living alone in new state with no psych help and a primary doc who got scared when I put out a feeler mentioning occasional depression. Unbelieveable! I study my diseases constantly and get new insights, but have no human contact. Mentioning BPD to ANYONE (even clergy) is a no-no. Ouch!

APR, 03, 2018 02:14:04 AM
For years I kept getting misdiagnosed with bipolar. I had to take matters into my own hands. I read through the whole DSM, read other books, did research online. Then finally I found BPD. The majority of the symptoms, I had. Oddly, I was relieved. Finally the way I felt and acted had a name. I felt hopeful because now I knew what was wrong with me. Now I could get help for it. The psychologist I see now, gave me a very thorough exam which asked various questions. I of course answered honestly. I wanted to confirm it is indeed BPD. Results came back: PTSD, Borderline Personality Disorder, and Major Depressive Disorder. After years of being left untreated and misdiagnosed, I'm making steps forward and getting the help I needed.

FEB, 09, 2018 03:50:48 AM
Danielle Gager
I have bipolar 2 and now I've been diagnosed with bpd. I have occasional ptsd flare ups from trauma in my life. Finding the right meds while also coping with fibromyalgia since age 19 along with chronic migraines and using Percocet and soma for my back I messed up in 2008 is very difficult. I'm very sensitive to meds physically.
I feel like I'm always searching for a med for my bipolar and bpd.
It's an on going process that will likely never end. Especially when I can't work and the insurance I have now won't even let me afford things like latuda which could work for me. I tried abilify and I warn you to be very careful. It can cause severe behavior and side effects they do not always tell you about.
When I have severe side effects I have it marked as allergy so they do not ever give it to me again. But I have a great new doctor. I'm finally seeing a psychiatrist and she listens well and tries to keep me from having the compulsive behavior I had on meds like abilify. I became a very dangerous sex addict on it. And had a lot of hypomanic episodes. I also felt like my legs could not sit still so I paced a lot right after taking it and then during the day I could not sit still so I self medicated with marijuana to calm my nerves. It killed my legs. But some people have good experiences on it and I wish them well.
I want to try latuda very bad! Depakote is doing poorly and kills my stomach and appetite which is moderate but not good. Plus you have to be careful what you take with it like Tylenol and aspirin. It's killing my stomach at only 750mgER so I'm so frustrated because it works for my migraines finally.
Just be open about side effects and any strange behavior you notice. And have patience. Bipolar is biological and bpd is behavioural behavioral. There are differences though it's hard to tell with bipolar 2. Find a good psychiatrist always and be open!
I'm here for questions or you can look me up

FEB, 02, 2018 07:17:54 AM
This is excellent. I have been struggling most (if not all) of my life before they even had eg ADD let alone so much more! Recently thoughrouly tested & came up with dx’s of both bipolar2 and borderline! I was told that it can be difficult sometimes to get meds right for this dual dx. Prior to this I was a “guinea pig” for well over 50 psych meds each of which had uncomfortable consequences, some dire. I am chemically sensitive anyway & leave it to me to always have the side effect that if listed is always listed last! Meanwhile I am good natured and hopeful! Thank you for being here! aka Lee

JAN, 02, 2018 01:12:53 PM
AnnMarie Klavins
Informative .

DEC, 10, 2017 08:01:17 PM
I was told that I had Borderline Personality Disorder for 20 years. A few doctors thought I was bi-polar, but I stopped going to those doctors! in 2012 I was hospitalized for 9 weeks with daily therapy by a team of therapists, psychiatrists and medical doctors. I told them, "I give up, I'm bi-polar with borderline Personality Disorder!" They said, "we'll see....." WELL... as the article says, it's a movie, not a snap-shot. Long story short, I am NEITHER! I have PTSD. go figure! life has made more sense in these past 5 years than in the 47 years prior (I am 52 years old now.)

NOV, 14, 2017 02:47:56 AM
In Virginia where do you go with no insurance? And how do you stop lying about how you've already gone? And also how do we lie so well and why do we do it? Thank you in advance for your time and consideration.

NOV, 05, 2017 10:56:27 AM
Great support thank you

JUL, 03, 2017 05:13:28 PM
Lori ,Shoemaker
I really wish the whole world would just stop trying to rush everything, even when writing, or texting please just write out the whole word it takes 2extra seconds to write bipolar disorder, or borderline personality seriously people slow down it's hard for people to remember all these abbreviations being thrown around.

JUL, 03, 2017 12:14:15 AM
Great info, but I am concerned, my husband I guess is bipolar. But seems to fall in both sides. So I guess this was not so though out. It's seems many real people who have to deal with it on a daily basics seems to see it just someone looking to come up with another DX. something more for insurance and drug companies can just aboard and charge more money for.
People with mental health issues have enough issues in their lives and don't need to be having more meds and being bounced around. They are people not rubber balls.
Sorry to rant, I'm sick of seeing love ones hurt because they feel as those it the "oh look another pill, we can try". How sick can they all get from it?????

JUL, 02, 2017 10:46:35 PM
Ronald Kohl
Response to Linda Thomas:
Linda, care-giving family members can often arrange with the patient to talk with the psychiatrist, assist with meds, etc., in exchange for something the patient values. Cooperation brings exchange; no cooperation, no exchange. Attendance at NAMI-affiliate meetings, interacting with people who have been there, can be helpful in determining your own course.

JUL, 01, 2017 06:32:16 PM
Alanon has been very helpful to me and available in most areas day and evening for family and friends of alcohol and drug users. These folks have been through it all and can help

JUN, 29, 2017 09:37:43 AM
Linda Thomas
In military service, my husband was DX'd as "Personality Disorder" . Discharged, he was DX'd by civilian MD as Bipolar. Thus, med change. Then new psych, new med. change. Thus has gone on 30 yrs now, with disasters from each med change, each psych's opinion. Wish new and old psychs would consult, wish all psychs would consult with person who knows patient well, since these patients lie, and believe their own lies.

JUN, 28, 2017 06:21:16 PM
Another excellent article. Spot on

JUN, 28, 2017 04:50:43 PM
Kathleen Powers
Can a person have a bipolar diagnosis AND a BPD one?

JUN, 27, 2017 04:11:14 AM
kim cook
Hello everyone
I have been dragging my feet getting here I have been trying to get my daughter to come in for some help,I am not have any luck i am completely cut out from her life and my grandson. We were all fine she took off 12/26/16 went to her biological mothers 2 blocks away she is in complete hideout and will not let me see my grandson diagnosed 7/15/16 with disorders at 13. He is taking medication and she has not for 10 yrs. She has bipolar manic aggressive disorder 2 / her bilogical mother has schizophrenia I am just sick about everything I was very sick for several months and did not see the onset of her illness until 1/10/17 she had been walking around preparing her plans for approx 10 months before i seen clearly what had happened . I need some group time. I am moving forward with my court case to have visitation with my grandson and possible guardianship with both
she has been hiding from all servers making things difficult, as of yesterday new information and praying she will have her court papers by Friday. This is the Eugene area correct? I need to find a family group meeting i thought I seen something for Tuesday nights however it said when school was in?? Im going to call the nami phone number in morning for info, unless anyone has info to share now? I plan to be active I just do not no how to handle her at this age 39? and as far out as she has gotten. I am her enemy and was being so aggressive i do not no who she is? and my grandson what is happening to him??

JUN, 25, 2017 10:05:42 PM
My experience in my own sickness has been exhausting...I'll be turning 48 this year although a psychiatrist shared with me my BPD almost 8 years ago...I've never plunged for knowledge until now...I thought I was just an overly sensitive person with absolutely no control over my emotions...My 27 year old daughter in my opinion is way worse...I have been thinking she was bipolar until I started paying attention more closely and realized my own "issues" in her...but then I realized she's not had my life's tragedies knock the wind out of her as I have...and knocked me down a level or two...she still has her angry....she still has a violence in her...I'm to tired...I feel like I have to detach from my only child and miss out on my granddaughters...just to save my own strength...Having come to these revelations I've tried reaching out to my shrink to help me navigate and he hasn't returned my call...I'm not going to go into how hurtful that is but....I'll try to find another Dr I guess... It just always seems conspiratorial because my family Dr doesn't get it? Doesn't see it? Always lost and trying to stay buoyant is just such a struggle and a real life *****er

JUN, 18, 2017 02:14:25 AM
I would contact your local Community Services Board, Social Services, or if the healthy spouse is elderly, then the Agency for Aging. Surely, the ER wouldn't release the patient if at risk...You could contact the ill spouse's therapist to voice your concerns, knowing that he/she will be unable to discuss the case due to HIPAA. Hope this helps.

JUN, 15, 2017 07:46:30 PM
Marina Madden
I need of a advocate for a family caregiver that has a spouse dealing with a disorder.. emergency services needed because they are releasing my family member and I'm worried we are not being supported with confident help!!!

JUN, 13, 2017 09:32:29 PM
Claudia Eyre
This is article does an excellent job of summarizing difficult aspects of differentiation between Bipolar Mood Disorder and the much stigmatized and much talked-about Borderline Personality Disorder. While the article provides some clear distinctions, in actuality, the patients and family need a very talented and discriminate, plus a primary care psychiatric doctor or nurse clinician or psychologist to actually give the diagnosis and to plan treatment. Both medications and CBT based and/or DBT-based therapy are required.

JUN, 12, 2017 11:26:48 PM
Lizanne Corbit
Succinct, helpful, and informative read. Having accessible information like this is so important because knowledge, and education are two of the biggest tools we have to fight stigma and misunderstanding. These two are tricky to differentiate between, even in the professional field. So allowing the general public to have access to this information is so wonderful.

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