What is Other Specified Personality Disorder?

OSPD is used when personality dysfunction is clear (problems in self and interpersonal functioning plus pathological personality traits) but the presentation is atypical, mixed across several PDs, or does not meet duration/threshold criteria for a specific DSM-5 personality disorder. Clinicians can specify the reason (e.g., “mixed personality features; persistent personality change after medical illness”).

Common presentations

• Mixed personality traits: features of borderline + avoidant + narcissistic traits without full criteria for any one disorder.
• Atypical presentations: personality pathology shaped by cultural or developmental factors that don’t match textbook criteria.
• Subthreshold but impairing traits: strong trait-related dysfunction that causes work/relationship problems yet falls short of formal PD duration/threshold.
• Personality change due to medical condition: where personality shifts are prominent but etiologically linked to a neurological/medical condition (specified separately if appropriate).

Why use the OSPD label?

• Allows clinicians to record clinically significant problems without forcing an inaccurate categorical label.
• Facilitates access to treatment, disability documentation, and care planning.
• Encourages formulation-based treatment rather than rigid checklist diagnoses.

Assessment — practical steps

1. Detailed clinical interview: developmental history, relationship patterns, occupational impact, trauma history.
2. Structured tools: Personality Inventory (e.g., PID-5), SCID-5-PD or alternative structured interviews to map trait profiles.
3. Collateral information: obtain family/employer/previous clinician input where possible.
4. Assess for comorbidity: mood, anxiety, substance use, PTSD and neurocognitive disorders.
5. Rule out medical/medication causes: thyroid, neuro conditions, substance effects that might mimic personality change.
6. Functional analysis & formulation: identify maintaining factors, triggers, strengths and goals for change.

Differential diagnosis & common confounds

Treatment principles

Treatment should be formulation-led, pragmatic and tailored to presenting problems and patient readiness.

• Collaborative formulation: Work with the person to build a shared understanding of patterns, triggers and goals.
• Phase-based approach: Stabilisation (safety, crisis management) → skill-building (emotion regulation, interpersonal effectiveness) → deeper schema/meaning work where appropriate.
• Integrate modalities: Combine evidence-based psychotherapies, case management, and medication when warranted for coexisting conditions.

Evidence-based psychotherapies commonly used

• Dialectical Behavior Therapy (DBT): For emotion dysregulation, self-harm, impulsivity.
• Mentalization-Based Therapy (MBT): For attachment-related problems and poor mentalizing.
• Schematherapy: For entrenched maladaptive schemas and chronic personality patterns.
• Transference-Focused Psychotherapy (TFP): For severe identity disturbance and relational patterns.
• Cognitive-Behavioural approaches: CBT adaptations for personality-related beliefs and behavioural change.
• Group therapies & skills training: Social skills, emotion regulation and interpersonal effectiveness groups.

Medication — role and cautions

No medication treats personality disorder itself; medications target symptom domains or comorbidities.

• Antidepressants — for comorbid depression or anxiety.
• Mood stabilisers (e.g., lithium, valproate) — where mood lability or impulsivity is prominent.
• Atypical antipsychotics — for transient psychotic symptoms, severe anger/agitation or comorbid psychotic disorders.
• Use minimal effective doses, monitor side effects, and combine with psychotherapeutic work.

Practical clinician tips

• Build strong therapeutic alliance — personality pathology often means mistrust; patience and consistent boundaries matter.
• Use clear contracts about goals, session structure and crisis plans.
• Set realistic expectations — personality change is gradual; celebrate small functional gains.
• Work in the client’s life context — involve family/partners when safe and consented.
• Prioritise safety — assess suicide/self-harm risk and have crisis pathways in place.

When to refer / red flags

• Severe self-harm, active suicide intent or frequent hospital admissions.
• Persistent psychotic symptoms or diagnostic uncertainty requiring specialist input.
• Complex comorbidity (severe substance dependence, neurocognitive decline) needing multidisciplinary care.

Key takeaways

• OSPD documents clinically significant personality pathology that does not fit a single named PD.
• Use structured assessment, collateral information and formulation to guide treatment.
• Prefer psychotherapy (DBT, MBT, schema therapy, CBT) tailored to presenting problems; use medications for symptom targets or comorbid conditions.
• Set realistic goals, emphasise safety and support, and use multidisciplinary care when needed.