F19.99
BillableOther psychoactive substance use, unspecified with unspecified psychoactive substance-induced disorder
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is F19.99 an HCC code?
Yes. F19.99 maps to Drug Use Disorder/Substance Use Disorder, Moderate/Severe under the CMS-HCC V28 risk adjustment model (and Drug/Alcohol Dependence 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 F19.99
For F19.99 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 F19.99 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
F19.99 is the ICD-10-CM diagnosis code for other psychoactive substance use, unspecified with unspecified psychoactive substance-induced disorder. A mental or behavioral disorder caused by psychoactive substance use where the specific type of disorder is not clearly documented or specified. F19.99 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, F19.99 maps to Drug Use Disorder/Substance Use Disorder, Moderate/Severe (HCC 137) with a community, non-dual, aged base RAF weight of 0.358. Under the older CMS-HCC V24 model, F19.99 maps to Drug/Alcohol Dependence (HCC 55) with a community, non-dual, aged base RAF weight of 0.334. 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.
This is a last-resort code; attempt to identify the specific substance-induced disorder when possible. Because F19.99 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 F19.99 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This is a last-resort code; attempt to identify the specific substance-induced disorder when possible
- •Request clarification from the provider about the nature of the substance-induced condition
Clinical Significance
Other psychoactive substance use, unspecified with unspecified substance-induced disorder is the least specific code in the F19.9X range, indicating both the substance use pattern and the induced disorder type are unspecified. While it still captures an HCC, it represents a significant documentation gap. This code should prompt aggressive provider querying to identify the specific substances used, the pattern of use (abuse vs. dependence), and the nature of the induced disorder.
Documentation Requirements
- ✓Documentation of psychoactive substance use with some induced disorder present
- ✓Attempt to identify the specific substance(s) through provider query
- ✓Attempt to specify the use pattern (use, abuse, or dependence) through provider query
- ✓Attempt to identify the specific induced disorder through provider query
- ✓Any available clinical details about the substance-related condition
- ✓Treatment plan documentation