ICD-10-CM F43.89

ICD-10 Code F43.89: Other reactions to severe stress

F43.89 is the ICD-10-CM code for other reactions to severe stress. DSM-5-TR uses it for other specified trauma- and stressor-related disorder.

Official description
Other reactions to severe stress
Billable
Yes
Parent category
F43.8 · Other reactions to severe stress
DSM-5-TR name
Other specified trauma- and stressor-related disorder

Verified against the FY2027 ICD-10-CM code set (CDC/NCHS and CMS), effective October 1, 2026 - September 30, 2027, on . Chapter 5: Mental, Behavioral and Neurodevelopmental disorders (F01-F99).

Coding notes for F43.89

  • Replaced the old F43.8 for billing on October 1, 2022
  • Use when you name a specific stress reaction that does not fit PTSD, acute stress, or adjustment disorder
  • Unspecified trauma- and stressor-related disorder is F43.9

What to document for medical necessity

Payers look for a record that supports the diagnosis and the level of care. For trauma and stress-related disorders that usually means:

  • The stressor or traumatic event and when it happened
  • Current symptoms and their duration, since timing separates several of these codes
  • A scored measure where one fits, such as the PCL-5
  • Functional impairment and any safety concerns
  • Treatment plan goals tied to the trauma-related symptoms

CPT codes often billed with F43.89

The ICD-10 code says why you are treating the client and the CPT code says what you did. These are the service codes most often paired with F43.89:

90791 · Psychiatric diagnostic evaluation (intake) 90834 · 45-minute individual psychotherapy 90837 · 60-minute individual psychotherapy

Free templates for this diagnosis

Related ICD-10 codes

F43.81 · Prolonged grief disorder F43.10 · Post-traumatic stress disorder, unspecified F43.0 · Acute stress reaction

Frequently asked questions

What replaced F43.8?

F43.8 was split into F43.81 (Prolonged grief disorder) and F43.89 (Other reactions to severe stress) on October 1, 2022.

What is the difference between F43.89 and F43.9?

F43.89 is other specified, where you state the reason the presentation does not fit another code. F43.9 is reaction to severe stress, unspecified.

This page is a coding reference, not clinical, diagnostic, billing, or legal advice. The diagnosis is the treating clinician's call, and payer rules vary - always confirm against the current ICD-10-CM code set and official guidelines and your payer's policy. See the full mental health ICD-10 code list.