What is the Hardest Mental Illness to Treat? (a comprehensive guide)

In this brief guide, we will try to answer the question “what is the hardest mental illness to treat?” as well as other questions related to mental illnesses, like what is the hardest mental illness to diagnose and what is the hardest mental illness to have.

What is the Hardest Mental Illness to Treat?

The hardest mental illness to treat is considered to be Borderline Personality Disorder, because it tends to encompass many aspects of the personality, particularly the emotional and interpersonal arena, which may often make it difficult to reach out to the person and to get them to keep taking treatment.

One of the most important things to treat any mental illness is compliance, whether than involves compliance to medication or to psychotherapy, and it has been seen that compliance may not necessarily be the strongest suit of this emotionally unstable personality.

If you’re facing this, it may be a good idea to seek the help of a therapist or other mental health professional. You can find a therapist at BetterHelp who can help you learn how to cope and address it.

It has also been reported that Borderline personality disorder is the hardest mental illness to treat because it tends to involve problematic interpersonal relationships, which may often extend to the therapist as well. But it is to take note, that there are many people who suffer from this mental illness.

Many therapists report that patients suffering from borderline personality disorder tend to open up very quickly, but then when things don’t go their way in therapy or they sense any sort of effort on the part of the therapist to cause change in their behavior or in their lifestyle, it can lead to them dropping out of therapy equally quickly and easily.

Another problem that often crops up in therapy with patients suffering from borderline personality disorder is the tendency of the patient to relate excessively to the therapist, and they may often get overly attached and not want to leave.

Often, borderline personality disorder can become one of the hardest mental illnesses to treat because as soon as they start nearing the middle of therapy, their fear of abandonment can creep in, and the therapist’s efforts may be met with a great deal of resistance.

Patients suffering from borderline personality disorder may also experience far too much of the therapeutic process known as transference, and while a healthy amount of transference is considered to be good for the therapeutic process, too much of it can lead to problems in the therapeutic relationship. 

There is a therapy for borderline personality disorder, however, that is actually based on the process of transference, and it is known as the Transference Based Psychotherapy, and it makes use of the transference mechanism that is so commonly seen in patients suffering from borderline personality disorder.

Lastly, one of the reasons why borderline personality disorder can be so hard to treat is that it often involves other problematic behaviors intertwined with the emotional instability and other issues the person has, like impulsive behaviors or depression, and a lot of time in therapy may often go towards solving these problems first.

Borderline Personality Disorder Test

Borderline personality disorder tests are not specialized and there isn’t anyone test that may be used for diagnostic purposes in the clinical setting, but other personality tests like the Millon Clinical Multiaxial Inventory is mostly used for the assessment of possible borderline personality disorder traits in an individual.

Millon Clinical Multiaxial Inventory is an objective personality test that measures various facets of the personality, and it also gives information about other mental illness conditions that a person might have, like depression or hypochondriasis.

MCMI also has lie and misrepresentation indexes that essentially measure the extent to which the person has tried to give answers that make them look good, and if these responses cross a certain cutoff, they are considered to be invalid forms and the test is done again.

Other than that, the extent of the exact problems of interpersonal relationships in the borderline personality may also be tested though the Thematic apperception test, a projective technique that measures the dynamic aspects of someone’s personality through their interpersonal relationships as well as their relationship with their environment.

If you want to take a borderline personality test it is recommended you go to a specialist, because online tests leave far too much to the answers of the person and if you think you have borderline personality disorder you may unintentionally give the answers that will prove it, and this kind of misdiagnosis can be problematic and dangerous.

However, if you think that someone you know has borderline personality disorder and you need a basic test to ascertain if their behavior fits the symptoms at all, here are some questions you can answer.

Read the statements given below and try to answer yes or no based on how often you have seen this individual act this way, and compare it to the scoring given after the statements:

  • Are their relationships extremely volatile?
  • Do they suffer from feelings of emptiness/complain of feeling like nothing matters or not feeling anything?
  • Do you feel that they constantly try to guilt people into doing things?
  • Do they get depressed often?
  • Do they have violent outbursts when they are fighting with someone?
  • Do they have extremely promiscuous behavior?
  • Are they afraid of being abandoned or do they seek constant reassurance of love and affection?
  • When in arguments, do they try to victimize themselves and make others the bad guy?
  • Do they have problems holding down jobs or maintaining a healthy academic life?
  • Do they ever self-harm?
  • Do they threaten suicide every time it seems that things are not going their way?
  • Do they often act impulsively without concern for consequences?
  • Do they have frequent breakups or problems in their romantic life?

If you answered yes to more than 8 questions, it may mean that the person is suffering from Borderline personality disorder, and they may need intervention to fix their patterns of behavior.

Borderline Personality Disorder: Signs and Symptoms 

The borderline personality disorder diagnostic criteria according to the Diagnostic and Statistical Manual is given as follows:

“BPD is a pervasive pattern of instability in interpersonal relationships, self-image, and emotion, as well as marked impulsivity beginning by early adulthood and present in a variety of contexts, as indicated by five (or more) of the following:

  • Chronic feelings of emptiness
  • Emotional instability in reaction to day-to-day events (e.g., intense episodic sadness, irritability, or anxiety usually lasting a few hours and only rarely more than a few days)
  • Frantic efforts to avoid real or imagined abandonment
  • Identity disturbance with markedly or persistently unstable self-image or sense of self
  • Impulsive behavior in at least two areas that are potentially self-damaging (e.g., spending, sex, substance abuse, reckless driving, binge-eating)
  • Inappropriate, intense anger or difficulty controlling anger (e.g., frequent displays of temper, constant anger, recurrent physical fights)
  • Pattern of unstable and intense interpersonal relationships characterized by extremes between idealization and devaluation (also known as “splitting”) Recurrent suicidal behavior, gestures, or threats, or self-harming behavior Transient, stress-related paranoid ideation or severe dissociative symptoms.”

Additionally, the ICD defines the Diagnostic criteria of Borderline Personality Disorder as follows:

“A personality disorder in which there is a marked tendency to act impulsively without consideration of the consequences, together with affective instability. The ability to plan ahead may be minimal, and outbursts of intense anger may often lead to violence or “behavioral explosions”; these are easily precipitated when impulsive acts are criticized or thwarted by others. Two variants of this personality disorder are specified, and both share this general theme of impulsiveness and lack of self-control.”

“Several of the characteristics of emotional instability are present; in addition, the patient’s own self-image, aims, and internal preferences (including sexual) are often unclear or disturbed. There are usually chronic feelings of emptiness. A liability to become involved in intense and unstable relationships may cause repeated emotional crises and may be

Associated with excessive efforts to avoid abandonment and a series of suicidal threats or acts of self-harm (although these may occur without obvious precipitants).”

What Causes Borderline Personality Disorder?

The main causes of borderline personality disorder have been thought to be physical, emotional or sexual abuse during the childhood or teenage years, which may lead to extremely skewed ideas of interpersonal relationships in the person.

There is some evidence of neural correlates of borderline personality disorder as well, and it has been found that the prefrontal cortex is not as active in this mental illness, implying impulsivity, and the amygdala and anterior cingulate cortex have been found to have increased activity, which signifies that they can be very emotionally labile.

Borderline personality disorder can also be a result of faulty learning patterns, and individuals who learn bad ways of relating to others from their parents or who are rewarded for attention seeking behavior or emotional outbursts as children, can often show traits of borderline personality disorder when they grow up.

Borderline Personality Disorder: Treatment

The treatment for Borderline Personality Disorder often consists of medication for any comorbid conditions they are suffering from at the given moment, and psychotherapy.

The psychotherapeutic approaches to borderline personality disorder may include the following:

  • Dialectical Behavior Therapy
  • Transference-Based Psychotherapy
  • Mentalization Based Psychotherapy
  • Cognitive Behavior Therapy

Out of these, Dialectical behavior therapy is one of the most preferred methods of psychotherapy for borderline personality disorder because it was created specifically for this condition by psychologist Dr. Marsha Linehan.

This type of psychotherapy consists of both individual and group sessions and it focuses on providing emotional stability to the individual to reduce some of the heightened emotional reactivity.

Transference based psychotherapy is a type of psychodynamic psychotherapy and it tries to employ the technique of transference between therapist and patient in order to teach them better ways of maintaining interpersonal relationships and helping to provide them with an outlet for their emotional reactions.

Mentalization based psychotherapy is aimed at reducing the impulsivity and emotional outbursts that the patient with borderline personality disorder experiences, and helping them visualize their actions in their mind before they engage in them.


In this brief guide, we tried to answer the question “what is the hardest mental illness to treat?” as well as other questions related to mental illnesses, like what is the hardest mental illness to diagnose and what is the hardest mental illness to have.

Some of the hardest mental illnesses to treat are those that have persisted for a long time or that begin when the person is still young, as any of these illnesses develop 

Frequently Asked Questions (FAQs): What is the hardest mental illness to treat?

What is the most difficult personality disorder to treat?

The most difficult personality disorder to treat has been considered to be Borderline personality disorder, but it has also been seen that almost all Cluster B personality disorders, that is histrionic, antisocial, and narcissistic personalities, can be rather hard to treat in certain circumstances.

What is considered the most debilitating mental disorder?

The most debilitating mental disorder is considered to be Schizophrenia because it is extremely severe and can affect general health, functioning, autonomy, subjective well being, and life satisfaction of those who suffer from it.

The constellation of symptoms in schizophrenia tends to encompass emotional, cognitive and behavioral components, and therefore it can affect all aspects of a person’s life, often leaving them incapable of carrying out their day to day functions with ease.

What are the top 5 mental illnesses?

The top 5 mental illnesses in America are given as follow:

Anxiety Disorders. 
Mood Disorders. 
Psychotic Disorders. 
Eating disorders.

What is the number 1 mental illness?

The number 1 mental illness that is currently affecting people the most across the world is Depression.
According to the WHO, depression is the number 1 mental illness according to prevalence, which is evident in the fact that it impacts an estimated 300 million people, and it has been established as the most common mental disorder and it generally affects women more often than men.

What are the top 3 mental illnesses?

The top 3 mental illnesses that affect people in America are:

Anxiety disorders. 
Major depressive disorder. 
Bipolar disorder. 




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