2026 ICD-10-CM Diagnosis Code F18.91Inhalant use, unspecified, in remission

ICD-10-CM Codes›F01–F99›F10-F19›F18

ICD-10-CM F18.91
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

F18.91 is a billable ICD-10-CM diagnosis code for inhalant use, unspecified, in remission. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 894 through 897. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Mental and substance use disorders in remission.

Code Identity

ICD-10-CM Code
F18.91
Billable Status
Yes — Valid for Submission
Code Describes
Inhalant use, unspecified, in remission
Short Description
Inhalant use, unspecified, in remission
Same as the full description in the CMS dataset.
Parent Code
F18.9
Inhalant use, unspecified

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF10-F19Mental and behavioral disorders due to psychoactive substance use
CategoryF18Inhalant related disorders
This CodeF18.91Inhalant use, unspecified, in remission

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Use(of)
      • inhalants
        • in remission

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MBD026
Mental and substance use disorders in remission
Default principal diagnosis: inpatient Yes · outpatient Yes

Code History & ChangesHistory

Replacement F18.91 replaces the following previously assigned code(s):

  • F18.90 - Inhalant use, unspecified, uncomplicated
FY 2023AddedAdded to the ICD-10-CM code setEffective October 1, 2022.
FY 2024–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About F18.91Overview

Is F18.91 (Inhalant use, unspecified) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report inhalant use, unspecified, in remission on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does F18.91 group to?

When inhalant use, unspecified, in remission is the principal diagnosis on an inpatient stay, it groups to MS-DRG 894, 895, 896, 897, with relative weights from 0.6169 to 1.7451 depending on complications. Higher weights mean higher Medicare reimbursement.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.