Working with clients who have fixed false beliefs can pose challenges in clinical practice. These cases require astute clinical skills, patience, compassion, and understanding. The complexity of these cases lay not just in the symptoms but also in how they affect the therapeutic relationship and treatment planning.

Delusional disorder presents unique challenges distinct from other psychotic conditions. Unlike more obvious symptoms, where one may be observed responding to internal stimuli, these clients can appear to function typically in most areas of life. This appearance of typical functioning can sometimes conceal the condition's severity, making accurate diagnosis and treatment planning very important.

Knowing the specific diagnostic criteria, coding requirements, and evidence-based interventions for delusional disorder is key for effective practice. The nuances of this condition require careful attention to clinical presentation and documentation. Let's look at the key aspects every clinician should know for these complex cases.

Overview of Delusional Disorder

Delusional Disorder (ICD-10 Code F22) falls under the ICD-10 category Delusional disorders and corresponds to Delusional Disorder in the DSM-5-TR. It represents a distinct psychotic condition characterized by one or more persistent, non-bizarre delusions lasting at least one month. These fixed beliefs, though false, involve situations that could occur in real life—such as being followed, poisoned, or secretly loved by someone.

Unlike schizophrenia, hallucinations are minimal or absent in delusional disorder. When they do occur, they are closely related to the delusional theme. Outside the delusional content, individuals typically maintain clear thinking, coherent speech, and relatively intact functioning in daily life. This preservation of personality and role performance often makes the disorder challenging to detect in clinical or social settings.

People with delusional disorder may continue to work, sustain relationships, and care for themselves effectively. Their delusional beliefs often surface only when specific topics arise or when stressors intensify their focus on those beliefs.

Subtypes and Clinical Presentation

Recognizing the specific subtypes of delusional disorder helps meet the client where they are at and guide treatment planning and risk assessment. Each subtype presents uniquely and requires tailored therapeutic approaches. The DSM-5-TR identifies several distinct presentations based on the predominant delusional theme.

• Persecutory: This common subtype involves beliefs of being harmed, conspired against, or persecuted. Clients may file lawsuits, become socially isolated, or act defensively. Assessing risk becomes important as anger and potential violence can emerge.
• Erotomanic: Clients believe someone, often of higher status, is in love with them despite no evidence. This can lead to stalking behaviors, repeated contact attempts, and legal complications. More common in females, these cases require careful boundary management.
• Grandiose: Features exaggerated beliefs about one's importance, power, knowledge, or special abilities. Clients might claim famous identities or secret missions, creating social disruption and treatment resistance.
• Jealous: Centers on unfounded beliefs about partner infidelity. More prevalent in males, this subtype carries elevated risk for domestic violence and requires immediate safety planning when identified.
• Somatic: Involves conviction of physical defects, illness, or infestation despite medical evidence to the contrary. These clients often seek multiple medical consultations, creating frustration when their concerns aren't validated.
• Mixed: Combines multiple themes without one predominating, requiring flexible treatment approaches.
• Unspecified Type: Used when the predominant delusional theme cannot be clearly determined or does not fit into the other specific types—for example, referential delusions without a prominent persecutory or grandiose component.
• Specifier – With Bizarre Content: Though not a specific type, this specifier applies when the delusions are clearly implausible, not understandable, and not derived from ordinary life experiences—for instance, the belief that one’s internal organs have been removed and replaced with someone else’s organs without any wounds or scars.

Before confirming diagnosis, clinicians must rule out psychosis secondary to substances or medical conditions through comprehensive assessment and medical history review. 

Assessment and Differential

A thorough evaluation of Delusional Disorder (ICD-10 F22) looks at three key dimensions: content, conviction, and impact on functioning. Document the specific beliefs, how strongly they’re held, and how they shape the person’s daily life. Note whether the delusional system stays confined to one domain (e.g., work, relationships) or extends across multiple areas.

Accurate diagnosis depends on teasing apart delusions from other conditions that can appear similar:

• Schizophrenia: Look for additional psychotic features such as hallucinations, disorganized speech or behavior, negative symptoms, or cognitive decline. Individuals with delusional disorder generally maintain clearer thinking and better overall functioning.
  
  
• Obsessive–Compulsive Disorder (OCD) with poor insight: Obsessions may appear delusional, but they typically involve doubt and internal conflict. True delusions are held with unwavering conviction and lack this inner resistance.
  
  
• Mood Disorders with psychotic features: In depression or bipolar disorder, delusions occur only during mood episodes. In delusional disorder, the beliefs persist regardless of mood state.
  
  
• Substance- or Medication-Induced Psychosis: When symptoms appear during intoxication or withdrawal and resolve with abstinence, a substance-related cause is more likely than delusional disorder.

Gathering collateral information is essential. Family members, employers, or other treatment providers can help clarify the onset, duration, and impact of the delusions—details that clients themselves may minimize or conceal.

Structured assessment tools can strengthen diagnostic accuracy. Instruments such as the Brown Assessment of Beliefs Scale (BABS) or the Peters Delusion Inventory (PDI) offer standardized ways to measure belief conviction, preoccupation, and insight. These measures not only guide treatment planning but also support clinical documentation for the F22 Delusional Disorder diagnosis.

Therapeutic Approach and Relationship Building

Building a strong therapeutic alliance is key to successful treatment with delusional disorder. Your approach should focus on empathy and non-confrontation, as directly challenging delusions often increases defensiveness and harms rapport. Concentrate on the distress these beliefs cause instead of disputing their validity. You cannot talk someone out of their delusion. At the same time you do not have to go with it.

Key principles for effective relationship building include:

• Genuine curiosity: Show sincere interest in understanding the client's experience without judgment. Ask questions like "How does this belief affect your daily life?" instead of challenging its accuracy.
• Validate emotions, not delusions: Recognize the real distress, fear, or frustration the client feels while staying neutral about the delusional content.
• Focus on practical goals: Work together on practical objectives like improving sleep, managing anxiety, or enhancing relationships rather than targeting the delusion directly.
• Consistency and reliability: Regular, predictable contact builds trust over time, which is especially important for clients with persecutory beliefs.

Cognitive Behavioral Therapy for psychosis (CBTp) is a specialized treatment approach that offers structured techniques for addressing the thinking patterns that maintain delusions. This approach explores how the client interprets experiences and develops alternative explanations without direct confrontation. Supportive therapy provides another valuable framework, emphasizing stress reduction and coping skills while maintaining the therapeutic relationship.

Consider addressing tangible needs early in treatment—helping with housing applications, medical appointments, or social services shows practical support. This builds rapport while improving overall functioning. Keep in mind that insight may develop gradually or remain limited; successful therapy often means reducing distress and improving quality of life and minimizing functional impairment rather than eliminating the delusional belief entirely.

Documentation and Coding Considerations

Accurate documentation of delusional disorder requires close attention to specific clinical details that support the F22 diagnosis code. Your notes should capture the complete clinical picture while maintaining objectivity and precision.

Key elements to record include:

• Subtype specification: Document the main delusional theme (persecutory, erotomanic, grandiose, jealous, somatic, or mixed) as this guides treatment planning and risk assessment.
• Content details: Use direct quotes when possible to capture the exact nature of delusional beliefs, their intensity, and how they appear in daily life.
• Risk assessment: Thoroughly document any potential for harm to self or others, especially with jealous or persecutory subtypes where violence risk increases.
• Functional impact: Note specific areas where delusions affect work, relationships, or self-care versus areas where functioning remains intact.
• Timeline and triggers: Record symptom duration (must exceed one month for F22), onset patterns, and environmental factors that worsen delusional thinking.
• Rule out other psychotic disorders: Document the absence of hallmark features of schizophrenia spectrum disorders—such as prominent hallucinations, disorganized speech or behavior, or negative symptoms. Clarify that functioning remains relatively intact outside of delusional content, which supports the F22 diagnostic distinction.

When bizarre delusions emerge or additional psychotic features develop, update the diagnostic code accordingly—this may indicate progression to schizophrenia (F20.0) or another psychotic disorder. Document any coexisting conditions that complicate treatment, such as substance use or mood disorders, using appropriate additional codes.

Coordination with psychiatry requires clear documentation of medication trials, responses, and side effects. Include notes about treatment planning discussions and any adjustments to pharmacological interventions. Regular communication ensures integrated care while your documentation provides the clinical justification for ongoing psychiatric involvement.

Key Takeaways

Delusional disorder involves a fixed belief system where the individual can usually maintain a high level of functioning in life. It differs from other diagnoses with psychosis and requires a careful therapeutic approach. The ability to function outside the delusional content sets it apart from other psychotic conditions, making accurate diagnosis and specialized treatment important.

Critical principles for effective practice include:

• Building a strong therapeutic alliance: Focus on empathy and understanding rather than confrontation. Directly challenging delusions can harm rapport and increase resistance, while exploring the associated distress builds trust and engagement.
• Comprehensive documentation: Record the specific subtype (persecutory, erotomanic, grandiose, jealous, somatic, mixed, or unspecific), the presence of bizarre content, detailed content of beliefs, functional impact, and risk factors. This supports the F22 diagnosis code and guides treatment planning.
• Integrated care improves outcomes: Collaborate with psychiatry for medication management, while psychotherapy addresses distress and functioning. Document all interdisciplinary communications and treatment responses.
• Focus on function rather than belief change: Successful therapy improves quality of life, reduces distress, and enhances coping skills without eliminating the delusion entirely. CBT techniques help develop alternative interpretations without direct confrontation.
• Ongoing risk assessment: Certain subtypes, particularly jealous and persecutory types, carry elevated risk for violence. Regular evaluation and safety planning protect both clients and potential victims.

Remember that insight may develop gradually or remain limited throughout treatment. The therapeutic goal centers on helping clients manage their symptoms' impact while maintaining dignity and respect for their experiences.