2026 ICD-10-CM Diagnosis Code F16.21Hallucinogen dependence, in remission

ICD-10-CM Codes›F01–F99›F10-F19›F16

ICD-10-CM F16.21
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

F16.21 is a billable ICD-10-CM diagnosis code for hallucinogen dependence, 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. Coders also document this condition as hallucinogen dependence in remission. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Mental and substance use disorders in remission.

Code Identity

ICD-10-CM Code
F16.21
Billable Status
Yes — Valid for Submission
Code Describes
Hallucinogen dependence, in remission
Short Description
Hallucinogen dependence, in remission
Same as the full description in the CMS dataset.
Parent Code
F16.2
Hallucinogen dependence

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF10-F19Mental and behavioral disorders due to psychoactive substance use
CategoryF16Hallucinogen related disorders
This CodeF16.21Hallucinogen dependence, in remission

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Hallucinogen dependence in remission

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Other hallucinogen use disorder, moderate, in early remission
  • Other hallucinogen use disorder, moderate, in sustained remission
  • Other hallucinogen use disorder, severe, in early remission
  • Other hallucinogen use disorder, severe, in sustained remission
  • Phencyclidine use disorder, moderate, in early remission
  • Phencyclidine use disorder, moderate, in sustained remission
  • Phencyclidine use disorder, severe, in early remission
  • Phencyclidine use disorder, severe, in sustained 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.

    • Dependence(on) (syndrome)
      • drug NEC
        • hallucinogen
          • in remission
    • Disorder(of)
      • hallucinogen use
        • moderate or severe
          • in remission (early) (sustained)
    • Disorder(of)
      • phencyclidine use
        • moderate or severe
          • in remission (early) (sustained)

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

Clinical InformationClinical

  • Hallucinogen Dependence

    a drug dependence for a hallucinogenic substance.

  • Hallucinogen Dependence with Hallucinogen Persisting Perception Disorder|Hallucinogen dependence with hallucinogen persisting perception disorder

    evidence of hallucinogen dependence with hallucinogen persisting perception disorder.

  • Hallucinogen Dependence with Hallucinogen-Induced Anxiety Disorder|Hallucinogen dependence with hallucinogen-induced anxiety disorder

    evidence of hallucinogen dependence with hallucinogen-induced anxiety disorder.

  • Hallucinogen Dependence with Hallucinogen-Induced Mood Disorder|Hallucinogen dependence with hallucinogen-induced mood disorder

    evidence of hallucinogen dependence with hallucinogen-induced mood disorder.

  • Hallucinogen Dependence with Hallucinogen-Induced Psychotic Disorder with Delusions|Hallucinogen dependence with hallucinogen-induced psychotic disorder with delusions

    evidence of hallucinogen dependence with hallucinogen-induced psychotic disorder with delusions.

  • Hallucinogen Dependence with Hallucinogen-Induced Psychotic Disorder with Hallucinations|Hallucinogen dependence with hallucinogen-induced psychotic disorder with hallucinations

    evidence of hallucinogen dependence with hallucinogen-induced psychotic disorder with hallucinations.

  • Hallucinogen Dependence with Hallucinogen-Induced Psychotic Disorder, Unspecified|Hallucinogen dependence with hallucinogen-induced psychotic disorder, unspecified

    evidence of hallucinogen dependence with hallucinogen-induced psychotic disorder.

  • Hallucinogen Dependence with Intoxication with Delirium|Hallucinogen dependence with intoxication with delirium

    evidence of hallucinogen dependence with intoxication with delirium.

  • Hallucinogen Dependence with Intoxication, Uncomplicated|Hallucinogen dependence with intoxication, uncomplicated

    evidence of hallucinogen dependence with intoxication, uncomplicated.

  • Hallucinogen Dependence with Intoxication, Unspecified|Hallucinogen dependence with intoxication, unspecified

    evidence of hallucinogen dependence with intoxication.

  • Hallucinogen Dependence with Other Hallucinogen-Induced Disorder|Hallucinogen dependence with other hallucinogen-induced disorder

    evidence of hallucinogen dependence with other hallucinogen-induced disorder.

  • Hallucinogen Dependence with Unspecified Hallucinogen-Induced Disorder|Hallucinogen dependence with unspecified hallucinogen-induced disorder

    evidence of hallucinogen dependence with unspecified hallucinogen-induced disorder.

  • Hallucinogen Dependence, Continuous Use

    physical and psychological dependence on hallucinogenics, which is associated with a pattern of continuous use.

  • Hallucinogen Dependence, Episodic Use

    physical and psychological dependence on hallucinogenics, which is associated with a pattern of episodic use.

  • Hallucinogen Dependence, in Remission|Hallucinogen dependence, in remission

    evidence of hallucinogen dependence, in remission.

  • Hallucinogen Dependence, Uncomplicated|Hallucinogen dependence, uncomplicated

    evidence of hallucinogen dependence, uncomplicated.

Patient EducationClinical

Drug Use and Addiction

Drugs are chemical substances that can change how your body and mind work. They include prescription medicines, over-the-counter medicines, alcohol, tobacco, and illegal drugs.

The full article covers:

  • What are drugs?
  • What is drug use?
  • What is drug addiction?
  • Does everyone who takes drugs become addicted?
  • Who is at risk for drug addiction?
  • What are the signs that someone has a drug problem?
  • What are the treatments for drug addiction?
  • Can drug use and addiction be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert F16.21 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
304.53 Hallucinogen dep-remiss
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About F16.21Overview

Is F16.21 (Hallucinogen dependence) a billable code?

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

What MS-DRG does F16.21 group to?

When hallucinogen dependence, 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.

What is the ICD-9 equivalent of F16.21?

Under the General Equivalence Mappings, hallucinogen dependence, in remission converts to ICD-9-CM 304.53 (hallucinogen dep-remiss). The mapping is a direct match.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.