Alphabetic Index FY2027

F16.94

Hallucinogen use, unspecified with hallucinogen-induced mood disorder

FY2027Chapter 5: Mental, Behavioral and Neurodevelopmental disorders/F10–F19 Mental and behavioral disorders due to psychoactive substance use

BillableComplete code, valid to report
Care settingsHome Health Primary · Behavioral HealthIPF Primary · MS-DRG 894–897

F16.94 (also written F1694) is a billable ICD-10-CM diagnosis code for hallucinogen use, unspecified with hallucinogen-induced mood disorder. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 40 codes in category F16 (Hallucinogen related disorders). The Alphabetic Index lists it under 5 entries. Its coding notes include 2 Excludes1 entries and 1 Excludes2 entry.

Guidelines tips

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

When use, abuse and dependence of the same substance are all documented, one code is assigned, by a set hierarchy.

Guidelines I.C.5.b.2Substance use, abuse and dependence: only one codeRead the official text

A medical condition due to substance use is coded from the Alphabetic Index along with the substance use, abuse or dependence code, not as a substance-induced disorder.

Guidelines I.C.5.b.4Medical conditions due to substance useRead the official text

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from F16.9 Hallucinogen use, unspecified

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (1 note)
Inherited from Chapter 5 Mental, Behavioral and Neurodevelopmental disorders
  • symptoms, signs and abnormal clinical laboratory findings, not elsewhere classified (R00-R99)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the Behavioral Health clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

IPF Primary

IPF MS-DRG adjustment. A principal diagnosis of this code groups to one of these MS-DRGs. Which one depends on other facts of the stay, so the factor is a range:

MS-DRGDescriptionFactor
894Alcohol/drug abuse or dependence, left AMA0.86
895Alcohol/drug abuse or dependence w rehabilitation therapy0.90
896Alcohol/drug abuse or dependence w/o rehabilitation therapy w MCC1.00
897Alcohol/drug abuse or dependence w/o rehabilitation therapy w/o MCC0.95
A principal diagnosis that groups to none of the 19 designated MS-DRGs gets no MS-DRG adjustment. Otherwise the claim still receives the federal per diem base rate and the other adjustments.

Source: CMS IPF PPS FY 2027 final rule (CMS-1847-F), Addendum A; code lists from the CMS MS-DRG Definitions Manual v44; effective for discharges on or after October 1, 2026

Includes

Further defines or gives examples of the content of the category.

Inherited from F16 Hallucinogen related disorders
  • ecstasy
  • PCP
  • phencyclidine
Also from chapter/block level (1 note)
Inherited from Chapter 5 Mental, Behavioral and Neurodevelopmental disorders
  • disorders of psychological development

Inclusion terms

Conditions classified to this code.

This code
  • Other hallucinogen induced bipolar or related disorder, without use disorder
  • Other hallucinogen induced depressive disorder, without use disorder
  • Phencyclidine induced bipolar or related disorder, without use disorder
  • Phencyclidine induced depressive disorder, without use disorder

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 5 entries