F18.251
BillableInhalant dependence with inhalant-induced psychotic disorder with hallucinations
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is F18.251 an HCC code?
Yes. F18.251 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 F18.251
For F18.251 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 F18.251 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
F18.251 is the ICD-10-CM diagnosis code for inhalant dependence with inhalant-induced psychotic disorder with hallucinations. A person who is dependent on inhalants and experiencing hallucinations as a result of their inhalant use, which is a form of psychotic disorder. F18.251 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, F18.251 maps to Drug/Alcohol Psychosis (HCC 135) with a community, non-dual, aged base RAF weight of 0.000. Under the older V24 model, F18.251 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.
Verify documentation confirms both inhalant dependence and active psychotic symptoms with hallucinations. Because F18.251 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 F18.251 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
Clinical Significance
Inhalant dependence with induced psychotic disorder with hallucinations captures patients experiencing perceptual disturbances (visual, auditory, or tactile hallucinations) caused by chronic inhalant neurotoxicity. Toluene-based solvents are particularly associated with hallucinations. This is a high-acuity condition mapping to the highest substance use HCC.
Documentation Requirements
- ✓Documentation of inhalant dependence
- ✓Specific hallucination type documented (visual, auditory, tactile)
- ✓Provider statement linking hallucinations to inhalant use
- ✓Mental status examination documenting hallucinations
- ✓Assessment of insight and safety
- ✓Neurological examination for other neurotoxic signs
- ✓Treatment plan for both dependence and psychosis