F43.0 — Acute stress reaction
F43.0 is a billable, specific ICD-10-CM code for acute stress reaction. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Acute crisis reaction
- Acute reaction to stress
- Combat and operational stress reaction
- Combat fatigue
- Crisis state
- Psychic shock
Other codes that can never be billed with F43.0
These codes carry an Excludes1 note pointing at F43.0. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading F43.0 alone.
Risk adjustment
F43.0 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
F43.0 is named in 18 Medicare coverage policies — 17 listing it as supporting medical necessity, and 1 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A52434Health and Behavior Assessment/Intervention – Medical Policy Articlenot covered
- A56614Billing and Coding: Psychiatric Inpatient Hospitalization
- A56645Billing and Coding: Controlled Substance Monitoring and Drugs of Abuse Testing
- A56850Billing and Coding: Psychiatric Partial Hospitalization Programs
How F43.0 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to F43.0.
- Battle exhaustion
- Combat fatigue
- Shellshock(current)
- Crisis›acute reaction
- Crisis›state(acute reaction)
- Delirium, delirious›exhaustion
- Exhaustion, exhaustive›battle
- Exhaustion, exhaustive›delirium
- Exhaustion, exhaustive›psychosis
- Fatigue›combat
- Fugue›reaction to exceptional stress(transient)
- Panic›reaction to exceptional stress(transient)
Related codes at this level
Codes that share F43. If F43.0 is not quite right, the correct code is usually one of these.
Questions about F43.0
- Is F43.0 a billable ICD-10-CM code?
- Yes. F43.0 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does F43.0 sit in the tabular list?
- Mental, Behavioral and Neurodevelopmental disorders (F01-F99), in the block Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders (F40-F48).