F16.159
BillableHallucinogen abuse with hallucinogen-induced psychotic disorder, unspecified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is F16.159 an HCC code?
Yes. F16.159 maps to Drug/Alcohol Psychosis under the CMS-HCC V28 risk adjustment model (and Drug/Alcohol Psychosis under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for F16.159
For F16.159 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed F16.159 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
F16.159 is the ICD-10-CM diagnosis code for hallucinogen abuse with hallucinogen-induced psychotic disorder, unspecified. Misuse of hallucinogenic drugs leading to a persistent psychotic disorder with unspecified psychotic features. F16.159 sits in the ICD-10-CM chapter for mental, behavioral and neurodevelopmental disorders (f01-f99), within the section covering mental and behavioral disorders due to psychoactive substance use (f10-f19).
Under the CMS-HCC V28 risk adjustment model, F16.159 maps to Drug/Alcohol Psychosis (HCC 135) with a community, non-dual, aged base RAF weight of 0.000. Under the older V24 model, F16.159 mapped to the same category but with a base RAF weight of 0.434 — V28 recalibrated weights across the entire model. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Use this code when hallucinogen-induced psychotic disorder is documented but the specific psychotic features are not detailed. Because F16.159 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for F16.159 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code when hallucinogen-induced psychotic disorder is documented but the specific psychotic features are not detailed
- •Attempt to obtain clarification on whether delusions, hallucinations, or other psychotic symptoms are present
Clinical Significance
Hallucinogen abuse with unspecified psychotic disorder indicates psychotic features from hallucinogen abuse that are not further characterized as delusions or hallucinations. While still mapping to the highest substance use HCC, this code represents a documentation gap. Provider queries should be initiated to specify the psychotic manifestation for stronger clinical documentation and audit defensibility.
Documentation Requirements
- ✓Documented hallucinogen abuse
- ✓Evidence of psychotic symptoms attributed to hallucinogen use
- ✓Query to provider to specify delusions vs. hallucinations
- ✓Documentation that psychosis is substance-induced and persists beyond expected intoxication effects
- ✓Psychiatric evaluation and treatment plan