F18.280
BillableInhalant dependence with inhalant-induced anxiety disorder
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is F18.280 an HCC code?
Yes. F18.280 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 F18.280
For F18.280 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 F18.280 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
F18.280 is the ICD-10-CM diagnosis code for inhalant dependence with inhalant-induced anxiety disorder. This code describes a person who is dependent on inhalant substances (like glue, paint thinner, or aerosols) and has developed an anxiety disorder as a direct result of their inhalant use. The anxiety symptoms are caused by and occur alongside the substance dependence. F18.280 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, F18.280 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, F18.280 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.
Verify documentation clearly states both inhalant dependence AND inhalant-induced anxiety disorder to justify this combination code; do not code if anxiety existed before inhalant use began. Because F18.280 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 F18.280 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify documentation clearly states both inhalant dependence AND inhalant-induced anxiety disorder to justify this combination code; do not code if anxiety existed before inhalant use began
- •This code includes the dependence component, so do not separately code F18.20 (inhalant dependence without disorder); the .280 specificity already captures the dependence status
Clinical Significance
Inhalant dependence with induced anxiety disorder captures anxiety symptoms directly caused by chronic inhalant exposure in a dependent patient. Inhalants disrupt GABAergic and glutamatergic neurotransmission, which can produce persistent anxiety that complicates both the dependence treatment and psychiatric management.
Documentation Requirements
- ✓Documentation of inhalant dependence
- ✓Specific anxiety symptoms documented
- ✓Provider statement that anxiety is induced by inhalant use
- ✓Temporal relationship between inhalant exposure and anxiety onset
- ✓Differentiation from primary anxiety disorders and withdrawal anxiety
- ✓Treatment plan addressing both conditions