F43.1

Post-traumatic stress disorder (PTSD)

Post-traumatic stress disorder (PTSD) is a complex psychiatric disorder that can occur in people who have experienced or witnessed a traumatic event, series of events, or set of circumstances. An individual may experience this as emotionally or physically harmful or life-threatening and it may affect mental, physical, social, and/or spiritual well-being. Clinically, it is characterized by four distinct symptom clusters: intrusion (flashbacks or nightmares), avoidance (staying away from reminders), negative alterations in cognitions and mood (persistent fear, guilt, or detachment), and alterations in arousal and reactivity (hypervigilance or sleep disturbances). Symptoms must persist for more than one month and cause significant distress or functional impairment. In the ICD-10-CM 2026 classification, F43.1 serves as the parent subcategory for more specific designations regarding the clinical duration and status of the disorder, distinguishing between acute, chronic, and unspecified manifestations.

Clinical Symptoms

  • Recurrent, involuntary, and intrusive distressing memories of the traumatic event
  • Recurrent distressing dreams or nightmares related to the trauma
  • Dissociative reactions (e.g., flashbacks) where the individual feels the event is recurring
  • Intense or prolonged psychological distress at exposure to internal or external cues
  • Marked physiological reactions to reminders of the traumatic event
  • Efforts to avoid distressing memories, thoughts, or feelings associated with the event
  • Avoidance of external reminders (people, places, conversations, activities, objects) of the trauma
  • Inability to remember an important aspect of the traumatic event
  • Persistent and exaggerated negative beliefs or expectations about oneself, others, or the world
  • Persistent, distorted cognitions about the cause or consequences of the event leading to self-blame
  • Persistent negative emotional state (e.g., fear, horror, anger, guilt, or shame)
  • Markedly diminished interest or participation in significant activities
  • Feelings of detachment or estrangement from others
  • Persistent inability to experience positive emotions
  • Irritable behavior and angry outbursts (with little or no provocation)
  • Reckless or self-destructive behavior
  • Hypervigilance and exaggerated startle response
  • Problems with concentration and sleep disturbance

Common Causes

  • Direct exposure to a traumatic event involving actual or threatened death, serious injury, or sexual violence
  • Witnessing, in person, the traumatic event(s) as it occurred to others
  • Learning that the traumatic event(s) occurred to a close family member or close friend
  • Experiencing repeated or extreme exposure to aversive details of the traumatic event(s) (e.g., first responders, police officers)
  • Combat exposure and military-related trauma
  • Childhood physical or emotional abuse and neglect
  • Sexual assault or physical battery
  • Kidnapping or being taken hostage
  • Terrorist attacks and mass casualty events
  • Natural or human-made disasters (e.g., earthquakes, floods, fires)
  • Severe motor vehicle accidents or industrial accidents
  • History of prior psychiatric conditions or lack of post-trauma social support
  • Genetic predisposition and family history of anxiety or depression

Documentation & Coding Tips

Distinguish between acute and chronic presentations to select the correct fourth character.

Example: Patient presents with intrusive memories and hyperarousal lasting 5 months following a motor vehicle accident. Diagnosis: Post-traumatic stress disorder, chronic (F43.12). Severity: Moderate symptoms impacting occupational performance. Plan: Initiate SSRI and trauma-focused therapy.

Billing Focus: Documentation must specify a symptom duration of 3 months or longer to justify the chronic code F43.12.

Document the specific traumatic event or exposure to support medical necessity for specialized psychotherapy.

Example: Patient reports recurrent distressing dreams and avoidance behavior following exposure to actual death during military service. Diagnosis: Post-traumatic stress disorder, chronic (F43.12). Associated with history of military combat trauma.

Billing Focus: The note must link the diagnosis to the inciting trauma to validate the use of psychotherapy codes 90834 or 90837.

Include all four symptom clusters: intrusion, avoidance, negative alterations in cognitions/mood, and alterations in arousal/reactivity.

Example: Patient exhibits flashbacks (intrusion), avoids the site of trauma (avoidance), expresses persistent negative beliefs about the self (cognition), and shows exaggerated startle response (arousal). Diagnosis: Post-traumatic stress disorder, chronic (F43.12).

Billing Focus: Comprehensive symptom documentation supports the medical decision making (MDM) complexity for higher-level E/M codes like 99214.

Explicitly state functional impairment in social, occupational, or other important areas of functioning.

Example: PTSD symptoms have resulted in the patient taking a leave of absence from work and social withdrawal from family members. Diagnosis: Post-traumatic stress disorder, chronic (F43.12). Functional status: Severe impairment.

Billing Focus: Functional impairment documentation justifies the necessity for frequent monitoring and intense therapeutic intervention.

Identify and document co-occurring conditions like substance use or depression as they frequently complicate PTSD management.

Example: Patient meets criteria for Post-traumatic stress disorder, chronic (F43.12) and Alcohol use disorder, moderate (F10.20). PTSD symptoms trigger alcohol cravings as a maladaptive coping mechanism.

Billing Focus: Reporting all managed conditions allows for proper coding of comorbidities that increase the complexity of the visit.

Relevant CPT Codes

Related Diagnoses

Hierarchy