ICD-10 Code F43.0 – Acute stress reaction (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F43.0 – Acute stress reaction
What it is
F43.0 identifies a short-term stress response that occurs soon after an overwhelming event. Use it when the record describes an acute reaction to severe stress, not a longer-lasting adjustment or anxiety disorder.
Clinical signs
Typical findings include emotional distress, anxiety, confusion, withdrawal, or a brief dissociative response after a traumatic event. Clinical features vary; refer to documentation.
When to use this code
Use F43.0 when documentation links the patient’s symptoms directly to an acute stressful event and the provider diagnoses acute stress reaction. It may fit after accidents, assaults, disasters, or other sudden threats. You should code from the provider’s stated diagnosis, not from stress alone.
Do not use for
Do not use this code for normal stress, uncomplicated grief, or conditions better described as adjustment disorder or post-traumatic stress disorder. Check documentation when the record is unclear.
Coding tip
Look for a documented acute stress diagnosis and the triggering event; if either is missing, query or code only what is clearly stated.