Skip to content
HCC Buddy home

F18.27 ICD-10-CM Code: Inhalant dependence with inhalant-induced dementia

F18.27 maps to CMS-HCC V28 135. A source-labeled RAF reference is available. Confirm the documented diagnosis and applicable coding requirements. MEAT criteria · RAF Calculator · free HCC coding tools

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupF18.27

FY 2026 Apr update / Mental, Behavioral and Neurodevelopmental disorders (F01-F99) / Mental and behavioral disorders due to psychoactive substance use (F10-F19)

F18.27

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Inhalant dependence with inhalant-induced dementia

A person dependent on inhalants who has developed dementia (permanent memory loss and cognitive decline) caused by their chronic inhalant abuse.

Buddy the Bee presenting code insight

Buddy Insight

Inhalant dependence with induced dementia is among the most severe inhalant-related diagnoses.

OverviewRisk ModelsCode BookDocumentationAuditNotesEdition comparison

CMS-HCC V28

HCC 135

Code-level coefficient reference

CMS-HCC V24

Historical

Historical

Not used for CY2026 payment

ACA/HHS

HCC 081

Code-level coefficient reference

ESRD/PACE

HCC 54

Code-level coefficient reference

RXHCC

N/A

—

Not mapped

Code Book Path

Official
F18Inhalant related disordersF18.2Inhalant dependenceF18.27Inhalant dependence with inhalant-induced dementia

Inclusion Terms

Official
  • Inhalant use disorder, moderate, with inhalant induced major neurocognitive disorder
  • Inhalant use disorder, severe, with inhalant induced major neurocognitive disorder

Excludes 2

Official
  • symptoms, signs and abnormal clinical laboratory findings, not elsewhere classified (R00-R99)Inherited from F01-F99

Related Codes

Official
F18.20Inhalant dependence, uncomplicatedF18.21Inhalant dependence, in remissionF18.22Inhalant dependence with intoxicationF18.24Inhalant dependence with inhalant-induced mood disorderF18.25Inhalant dependence with inhalant-induced psychotic disorder

Includes

Official
  • disorders of psychological developmentInherited from F01-F99, F18
  • volatile solventsInherited from F01-F99, F18

Excludes 1

Official
  • inhalant abuse (F18.1-)Inherited from F18.2
  • inhalant use, unspecified (F18.9-)Inherited from F18.2

Code First

Official

No Code First sequencing instructions are included in this display for F18.27. Check the code and parent instructions in the Code Book.

Use Additional

Official

No Use Additional Code instructions are included in this display for F18.27. Check the code and parent instructions in the Code Book.

Code Also

Official

No Code Also instructions are included in this display for F18.27. Check the code and parent instructions in the Code Book.

Buddy Documentation Tip

HCC Buddy guidance
Documentation of inhalant dependence
Formal cognitive assessment demonstrating dementia (MMSE, MoCA, or neuropsychological battery)
Provider statement linking dementia to chronic inhalant use
Brain MRI showing white matter changes, cerebellar atrophy, or basal ganglia damage

MEAT Support

HCC Buddy guidance
Documentation of inhalant dependence
Formal cognitive assessment demonstrating dementia (MMSE, MoCA, or neuropsychological battery)
Provider statement linking dementia to chronic inhalant use
Brain MRI showing white matter changes, cerebellar atrophy, or basal ganglia damage

Audit Caution

HCC Buddy guidance
Not linking dementia to inhalant use, coding primary dementia instead
Missing the diagnosis because inhalant dementia affects younger patients than typical dementia
Confusing chronic cognitive effects with acute intoxication impairment
Not obtaining formal neurocognitive testing to support the diagnosis

Common Mistakes

HCC Buddy guidance
F18.17 — Inhalant abuse with induced dementia; use when abuse rather than dependence
F18.97 — Inhalant use, unspecified with induced dementia; less specific use pattern
F03.90 — Unspecified dementia; use for dementia of unknown cause
F02.80 — Dementia in other diseases; used with underlying condition code

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is F18.27 an HCC code?

Yes. F18.27 (Inhalant dependence with inhalant-induced dementia) maps to HCC 135, Drug Use with Psychotic Complications under the CMS-HCC V28 risk adjustment model, with a source-labeled community non-dual aged reference coefficient of 0.424. Source-labeled code-level coefficients are references, not member totals. Actual contribution depends on complete member context, hierarchy and cleanup rules, interactions, and model year. HCC Buddy's RAF Calculator supports CMS-HCC V28 PY2026 and shows no score unless every required source and calculation check passes. It is billable for payment year 2026.

Coder answer: F18.27 is billable and maps to V28 HCC 135, Drug Use with Psychotic Complications. Open it in the Code Book for the tabular path, RAF, and MEAT checklist.

Code
F18.27
Description
Inhalant dependence with inhalant-induced dementia
HCC (V28)
HCC 135 — Drug Use with Psychotic Complications
RAF reference coefficient
0.424
Billable
Yes
Payment year
2026

HCC Category Mapping

V28HCC 135, Drug Use with Psychotic Complications
0.424
ESRDHCC 54, Substance Use with Psychotic Complications
Not separately weighted

These are source-labeled model coefficients, not member totals. A category may still be removed by hierarchy or model cleanup rules. Weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. Actual per-patient RAF contribution depends on member context, hierarchy and cleanup rules, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains available for historical review.

Work F18.27 in the Code Book — tabular path, V28 RAF reference, and MEAT checklist →

MEAT review for F18.27

For F18.27, confirm that the documentation supports the diagnosis and meets the applicable coding, encounter, program and payer requirements. MEAT (Monitor, Evaluate, Assess, or Treat) is a review mnemonic, not a universal CMS coding rule.

  • 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

Coder workflow notes

Get the V28 mapping + MEAT cheat sheet

One printable reference: check representative V28 mappings and the documentation reminders your note needs. Free, no card.

Free PDF. No card. Unsubscribe anytime.

What This Code Means

F18.27 is the ICD-10-CM diagnosis code for inhalant dependence with inhalant-induced dementia. A person dependent on inhalants who has developed dementia (permanent memory loss and cognitive decline) caused by their chronic inhalant abuse. F18.27 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, F18.27 maps to Drug Use with Psychotic Complications (HCC 135) with a source-labeled community, non-dual, aged reference coefficient of 0.424. No V24 mapping is shown for F18.27; use the applicable model and payment year when reviewing the V28 mapping. For CY2026 non-PACE Medicare Advantage, CMS uses 100% of the 2024 CMS-HCC model (V28). PACE uses a separate model blend. Source-labeled code-level coefficients are references, not member totals. Actual contribution depends on complete member context, hierarchy and cleanup rules, interactions, and model year. HCC Buddy's RAF Calculator supports CMS-HCC V28 PY2026 and shows no score unless every required source and calculation check passes.

Document the causal relationship between inhalant dependence and dementia development. For F18.27, confirm that the documentation supports the diagnosis and meets the applicable coding, encounter, program and payer requirements. MEAT (Monitor, Evaluate, Assess, or Treat) is a review mnemonic, not a universal CMS coding rule. 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, source-labeled coefficient references, and MEAT documentation criteria for F18.27 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

  • •Document the causal relationship between inhalant dependence and dementia development
  • •This represents permanent cognitive damage from inhalant exposure, not temporary intoxication effects

Clinical Significance

Inhalant dependence with induced dementia is among the most severe inhalant-related diagnoses. Chronic exposure to toluene and other volatile solvents causes progressive white matter destruction, leading to irreversible cognitive decline, memory loss, and functional impairment. These patients require long-term custodial care and intensive medical support.

Documentation Requirements

  • ✓Documentation of inhalant dependence
  • ✓Formal cognitive assessment demonstrating dementia (MMSE, MoCA, or neuropsychological battery)
  • ✓Provider statement linking dementia to chronic inhalant use
  • ✓Brain MRI showing white matter changes, cerebellar atrophy, or basal ganglia damage
  • ✓Functional assessment documenting impact on daily activities
  • ✓Timeline of cognitive decline relative to inhalant use history
  • ✓Differentiation from other dementia etiologies

Commonly Confused Codes

  • •F18.17: Inhalant abuse with induced dementia; use when abuse rather than dependence
  • •F18.97: Inhalant use, unspecified with induced dementia; less specific use pattern
  • •F03.90: Unspecified dementia; use for dementia of unknown cause
  • •F02.80: Dementia in other diseases; used with underlying condition code

Child Codes

F18.20Inhalant dependence, uncomplicated
HCC 137
F18.21Inhalant dependence, in remission
HCC 137
F18.22Inhalant dependence with intoxication
F18.24Inhalant dependence with inhalant-induced mood disorder
HCC 137
F18.25Inhalant dependence with inhalant-induced psychotic disorder
F18.27Inhalant dependence with inhalant-induced dementia
HCC 135
F18.28Inhalant dependence with other inhalant-induced disorders
F18.29Inhalant dependence with unspecified inhalant-induced disorder
HCC 137

Code Hierarchy

└F18Inhalant related disorders└F18.2Inhalant dependence└F18.27Inhalant dependence with inhalant-induced dementia
└F18.27Inhalant dependence with inhalant-induced dementia

For F18.27, confirm that the documentation supports the diagnosis and meets the applicable coding, encounter, program and payer requirements. MEAT (Monitor, Evaluate, Assess, or Treat) is a review mnemonic, not a universal CMS coding rule.

F18.27 maps to CMS-HCC V28 category 135, Drug Use with Psychotic Complications. See the ICD-10 to HCC mapping hub for how the V28 crosswalk works. The mapping identifies a payment HCC category for F18.27. Review its source-labeled HCC coefficient above, check the RAF Calculator with complete member context for CMS-HCC V28 PY2026, and confirm the documentation the chart needs before the code is submitted. HCC Buddy shows no RAF score unless every required source and calculation check passes.

Work F18.27 in HCC Buddy

Open F18.27 in the Code Book for the full Index-to-Tabular path, MEAT checklist, and V28 HCC mapping, or in the Encoder to code from a keyword search. Pro includes 7 days to try everything, no card required.

Open in Code BookOpen in EncoderStart Pro