Accurate identification and diagnosis of anxiety disorders are fundamental aspects of effective mental health treatment. The International Classification of Diseases, 10th Revision (ICD-10-CM) provides clinicians a structured way to classify various anxiety disorders, enabling precise documentation, effective communication, accurate reimbursement, and improved patient care.

This guide takes clinicians through key ICD-10 anxiety diagnoses, clearly summarizing criteria, symptoms, and coding distinctions.

Phobic Anxiety Disorders (ICD-10 category F40.x)

Phobic disorders involve excessive or unreasonable fears triggered by specific objects or situations and marked by active avoidant behaviors.

Commonly coded phobic disorders include:

1. Agoraphobia

• Agoraphobia with Panic Disorder (F40.01):

  • Fear of situations where escape/help might be difficult (open spaces, crowds, leaving home).

  • Frequent, recurrent panic attacks occur, driving avoidance behaviors.

  • Do not use separate panic disorder code (F41.0).

• Agoraphobia without Panic Disorder (F40.02):

  • Strong fear and avoidance of places/situations without panic attacks.

2. Social Phobia (Social Anxiety Disorder)

• Social Phobia, Unspecified (F40.10):

  • Excessive, persistent fear of social scrutiny or embarrassment in at least one social situation but less pervasive.

• Social Phobia, Generalized (F40.11):

  • Marked fear and avoidance spanning many or most social situations, significantly impairing life functions (work, relationships).

3. Specific (Isolated) Phobia (F40.2x)

• Clearly defined fear and avoidance of a particular object or situation.

Common specific phobia subtypes:

• Animal type (F40.218): e.g., spiders, dogs

• Natural/environmental type (F40.228): e.g., heights, storms

• Blood-injection-injury type (F40.23)

• Situational type (F40.24): e.g., elevators, flying

• Other or Unspecified type (F40.298): used if subtype is unclear

Other Anxiety Disorders (ICD-10 category F41.x)

These refer to anxiety disorders not confined to specific phobic objects or social settings.

1. Panic Disorder (F41.0)

• Recurrent, unexpected panic attacks involving intense fear or discomfort lasting several minutes.

• Symptoms include rapid heartbeat, sweating, dizziness, shortness of breath, chest pain, and fear of losing control or dying.

• Attacks must not consistently occur solely in particular feared situations (otherwise it suggests a phobia).

2. Generalized Anxiety Disorder (F41.1)

• Excessive anxiety and worry about various situations lasting at least six months.

• Associated symptoms: restlessness, fatigue, concentration problems, irritability, muscle tension, or sleep disturbances.

3. Mixed Anxiety and Depressive Disorder (F41.2)

• Persistent (at least one month) co-occurrence of anxiety and depressive symptoms.

• Neither condition meets full diagnostic criteria for GAD, panic disorder, depression, or other distinct disorders.

• Typically used in primary care settings.

4. Other Specified Anxiety Disorder (F41.8)

• Clearly documented anxiety conditions not fitting standard ICD-10 categories.

• Examples include: test anxiety, performance anxiety, culturally specific anxiety syndromes.

5. Anxiety Disorder, Unspecified (F41.9)

• Anxiety is clearly present, but definitive symptoms not yet fully clarified.

• Used in early evaluation stages or when limited information is available.

Determining Anxiety Disorder Due to Medical or Substance Use Causes

These are not coded under F40–F41 but are documented elsewhere as applicable.

• Anxiety due to a physiological medical condition (F06.4):

  • Anxiety directly linked to a medical issue (e.g., hyperthyroidism, arrhythmia).

  • Always document the underlying condition clearly.

• Substance-Induced Anxiety Disorders (F10–F19):

  • Anxiety symptoms triggered by intoxication or withdrawal.

  • Examples:

    • Alcohol-induced anxiety (F10.180)

    • Cannabis-induced anxiety (F12.180)

    • Stimulant-induced anxiety (F15.180)

• Adjustment Disorder with Anxiety (F43.22):

  • Anxiety arises in response to a clear psychosocial stressor (e.g., divorce, job loss), typically within three months.

  • Symptoms must not meet criteria for other distinct anxiety diagnoses.

Best Practices for Coding and Documentation

Clarity and precision are essential in clinical documentation and ICD-10 coding:

• Ensure documented symptoms clearly align with diagnostic criteria.

• Select the most specific ICD-10 codes available and provide symptom context (e.g., type of phobia, presence of panic attacks).

• Clearly differentiate primary anxiety disorders from those induced by medical or substance-related causes.

• Avoid excessive use of unspecified codes (F41.9) unless truly appropriate during early evaluations.

Common Mistakes to Avoid

• Incorrect use of unspecified codes (F41.9) when a more specific diagnosis is clearly supported.

• Mislabeling medically- or substance-induced anxiety as primary anxiety disorder.

• Failing to differentiate between panic disorder and agoraphobia variants.

• Insufficient documentation to justify diagnosis—especially when clinical criteria are not clearly outlined.

Quick Reference Coding Summary

Agoraphobia with Panic Disorder – F40.01

• Agoraphobia without Panic Disorder – F40.02

• Social Phobia, Generalized – F40.11

• Specific Phobia – Animal Type – F40.218

• Specific Phobia – Situational Type – F40.24

• Panic Disorder – F41.0

• Generalized Anxiety Disorder – F41.1

• Mixed Anxiety and Depressive Disorder – F41.2

• Other Specified Anxiety Disorder – F41.8

• Anxiety Disorder, Unspecified – F41.9

• Medical Condition-Induced Anxiety – F06.4

• Substance-Induced Anxiety (e.g., Alcohol) – F10.180

• Adjustment Disorder with Anxiety – F43.22

Key Takeaways

• ICD-10 coding precision is essential for clinical care, documentation integrity, and proper reimbursement.

• Always align diagnostic codes with clearly documented clinical criteria.

• Be mindful to differentiate primary, medically-induced, and substance-induced anxiety accurately.

• Minimize use of vague codes—opt for specificity whenever clinical data allows.

• Keep up with annual ICD-10-CM updates to ensure ongoing accuracy.

Final Note and Disclaimer

This guide provides concise clinical information to assist with accurate coding and documentation of anxiety disorders. It is not a substitute for full diagnostic manuals or clinical judgment. Always consult authoritative ICD-10 coding references and professional guidelines when making final coding decisions.