Cluster A personality disorders

Samir Kadri
Author: Samir Kadri Medical Reviewer: Morgan Blair Last updated:

Personality disorders are a class of mental health conditions marked by dysfunctional patterns of behaviors, thoughts and experiences which deviate from social and cultural norms. The DSM-5 recognizes ten different personality disorders, which can be grouped into three clusters differentiated by certain characteristics. These are known as Cluster A, Cluster B and Cluster C. [1]

What are Cluster A personality disorders?

Cluster A personality disorders are characterized by odd, eccentric, and unusual behavior, with sufferers finding everyday tasks and problems disproportionately challenging. Though living with a Cluster A personality disorder can feel stressful and overwhelming, with proper treatment sufferers can lead fulfilling lives.

The following article will explore different types of Cluster A personality disorders, the ways they differ from other personality disorders, how they are caused and diagnosed and treatment options available.

Types of Cluster A personality disorders

People with Cluster A personality disorders typically display strange and eccentric behavior that can cause them to struggle with everyday tasks and activities. There are three main types of Cluster A personality disorders: [1]

  • Paranoid personality pisorder (PPD): People with this personality disorder are unreasonably distrustful of other people’s actions and potential motives. They often interpret the intentions of others as malevolent and are unwilling to engage with them [2].
  • Schizoid personality disorder (SPD): People with SPD show a lack of interest in developing interpersonal relationships, struggle to express their emotions and detach themselves from wider society. They often prefer solitary activities and have little interest in sexual encounters with others [3].
  • Schizotypal personality disorder (STPD): STPD is typically characterized by eccentric behavior, odd beliefs and an all-round peculiar approach to life. Sufferers often do not grasp how people form relationships and how their behavior impacts other people. They struggle with social cues, misinterpret other people’s motives and as a result, often avoid fraternizing with people outside of their immediate family. They may also have odd, disorganized speech or thinking patterns [4].

How do Cluster A personality disorders differ from other types of personality disorders?

Cluster A personality disorders differ from other personality disorders in the way sufferers present symptoms. These individuals often display odd or eccentric behavior and may have difficulty forming close relationships due to their social and emotional detachment. [1]

In contrast, Cluster B personality disorders, including borderline, narcissistic, histrionic, and antisocial personality disorders, are characterized by dramatic, erratic, and emotional dysregulation. Sufferer’s actions are typically impulsive and underpinned by emotional stability, making it challenging for them to forge and maintain relationships.

Cluster C personality disorders differ from both Cluster A and Cluster B as these are marked by anxious and fearful traits. Individuals with Cluster C disorders tend to be hypervigilant, anxious, and consumed by fears of inadequacy and low self-worth.

What causes Cluster A personality disorders?

It is not known what specifically causes Cluster A personality disorders, however it is believed to be a combination of genetic, environmental, and neurobiological factors.

Known risk factors include childhood trauma, a family history of personality disorders and abnormalities in neural function. [5]

It must be emphasized that these risk factors are not specific to Cluster A personality disorders and diagnosis ought to be carried out by a trained mental health professional.

How are Cluster A personality disorders diagnosed?

To get diagnosed with a cluster A personality disorder, you will need to make an appointment with a mental health professional, such as a psychiatrist, psychologist, or therapist. They will conduct a thorough assessment of your psychological health, which may involve examining your medical history, questioning you about your symptoms and a range of tests.

You will be assessed against the criteria laid out in the DSM-5 for a range of disorders and if the doctor believes you have a Cluster A personality disorder, they will provide you with a diagnosis.

How are Cluster A personality disorders treated?

Once a diagnosis is made, the mental health professional will work with you to develop an appropriate treatment plan, which may include psychotherapy, medication, or other interventions tailored to the specific personality disorder. A range of treatment plans for Cluster A personality disorders are outlined below:


Psychotherapy is the frontline treatment for cluster A personality disorders, with cogntitive behavioral therapy (CBT) and dialectical behavior therapy (DBT) among the most popular choices. Both focus on encouraging individuals to recognize their maladaptive cognitive and behavioral patterns, and over time consciously choose to create more positive outcomes for themselves.

Group therapy can also prove beneficial to sufferers of Cluster A personality disorders, giving people the chance to engage socially in a supportive environment [6]. Whilst this may initially feel taxing, over time sufferers will garner a better understanding of their personality disorder and be better equipped to overcome their symptoms.


While no medication is FDA approved specifically to treat cluster A personality disorders, certain medications could be used to treat specific symptoms of an individual’s condition. For example, antipsychotics may be used to treat certain symptoms of schizotypal personality disorder, such as delusions or hallucinations [7].


Self-help techniques can be used at home to support therapeutic intervention, with meditation, yoga, regular exercise and a balanced diet all positive implementations into your life. They can help you manage stress and anxiety, better equipping you to combat your personality disorder and nourishing your overall sense of wellbeing. [6]

Mindfulness, central to DBT, can be practiced at home and helps you become more aware of the present moment. You will learn to focus on one problem at a time and refrain from judging yourself or others. This can be useful in addressing the social concerns that accompany Cluster A personality disorders.

  1. Overview of Personality Disorders – Psychiatric Disorders. (n.d.). MSD Manual Professional Edition.
  2. Paranoid Personality Disorder (PPD) – Psychiatric Disorders. (n.d.). MSD Manual Professional Edition. Retrieved September 25, 2023, from
  3.  Schizoid Personality Disorder (ScPD) – Psychiatric Disorders. (n.d.). MSD Manual Professional Edition. Retrieved September 25, 2023, from
  4. Schizotypal Personality Disorder (STPD) – Psychiatric Disorders. (n.d.). MSD Manual Professional Edition.
  5. American Psychological Association. (2010). What causes personality disorders?
  6. Robitz, R. (2013). What Are Personality Disorders? American Psychiatric Association.
  7. Koch, J., Modesitt, T., Palmer, M., Ward, S., Martin, B., Wyatt, R., & Thomas, C. (2016). Review of pharmacologic treatment in cluster A personality disorders. Mental Health Clinician, 6(2), 75–81.
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Samir Kadri
Author Samir Kadri Writer

Samir Kadri is a medical writer with a non-profit sector background, committed to raising awareness about mental health.

Published: Sep 25th 2023, Last edited: Feb 29th 2024

Morgan Blair
Medical Reviewer Morgan Blair MA, LPCC

Morgan Blair is a licensed therapist, writer and medical reviewer, holding a master’s degree in clinical mental health counseling from Northwestern University.

Content reviewed by a medical professional. Last reviewed: Sep 25th 2023