F16.121 Hallucinogen abuse with intoxication with delirium

The ICD-10-CM code for Hallucinogen abuse with intoxication with delirium is F16.121 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

5: Mental, Behavioral and Neurodevelopmental disorders (F01-F99)

Section

F10-F19: Mental and behavioral disorders due to psychoactive substance use (F10-F19)

Category F16

53 codes (40 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to F16.121:

• Delirium, delirious (acute or subacute) (not alcohol- or drug-induced) › due to (secondary to) › phencyclidine intoxication (acute) › in › abuse
• Disorder (of) › phencyclidine use › mild › with › phencyclidine intoxication delirium
• Delirium, delirious (acute or subacute) (not alcohol- or drug-induced) › due to (secondary to) › hallucinogen intoxication › in › abuse
• Disorder (of) › hallucinogen use › mild › with › hallucinogen intoxication delirium
• Abuse › drug NEC (non-dependent) › hallucinogen › with › intoxication › with › delirium

U.S. Hospital Utilization

• An estimated 115 U.S. inpatient stays in 2023 included F16.121 among the documented diagnoses.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Pain disorders related to psychological factors (TOC entry)

a. Pain disorders related to psychological factors ..................................................................... 43

Psychoactive substance use disorders (TOC entry)

b. Mental and behavioral disorders due to psychoactive substance use ................................... 43

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)