F11 vs Z79.85

F11 (Opioid related disorders) compared with Z79.85 (Long-term (current) use of injectable non-insulin antidiabetic drugs), from the official CMS tabular data.

Summary

These codes can be reported together when both conditions are documented, because Z79.85 lists F11 under Excludes2, which marks them as distinct conditions.

Official rule

What is different?

The conditions named, billing status and chapter.F11 is “Opioid related disorders”; Z79.85 is “Long-term (current) use of injectable non-insulin antidiabetic drugs”. F11 is a non-billable header; Z79.85 is billable. F11 sits in F01-F99 — Mental, Behavioral and Neurodevelopmental Disorders (F01-F99); Z79.85 in Z00-Z99 — Factors Influencing Health Status and Contact with Health Services (Z00-Z99).

Registry fact

Can these codes be reported together?

Yes, when both are documented.Z79.85 lists F11 under Excludes2: “drug abuse and dependence (F11-F19)”. Excludes2 marks distinct conditions that may both be reported when both are documented.

Official ruleGuide: Excludes1 vs Excludes2

Is there an Excludes1 relationship?

None.Neither entry carries an Excludes1 note that names the other code.

Official rule

Is there an Excludes2 relationship?

Yes.Z79.85’s tabular entry: “drug abuse and dependence (F11-F19)”. The note covers F11.

Official ruleGuide: Excludes1 vs Excludes2

Is one more specific?

Not comparable.The codes sit in different categories; specificity is only comparable within one category.

Is one a parent or header code?

One is a header.F11 is a non-billable header, but Z79.85 is not one of its subdivisions.

Registry fact

Are there sequencing instructions?

None.Neither entry carries a Code First or Use Additional Code note that names the other.

Official rule

Are there other coding relationships?

None found.No laterality, encounter-phase, Table of Neoplasms, Table of Drugs and Chemicals, or history-versus-active-disease relationship links these codes.

MedCoder-derived

Official rule: a tabular instructional note or a section of the ICD-10-CM Official Guidelines, quoted as published. Registry fact: the codes’ own published attributes (titles, billable status, position in the hierarchy, code set). MedCoder-derived: a reading MedCoder computes from those facts; it is not itself a rule. How to read the labels

Can these codes be reported together?

Informational

Excludes2 relationship

Z79.85

Long-term (current) use of injectable non-insulin antidiabetic drugs

↔

F11

Opioid related disorders

What we found

Yes, when both are documented.Z79.85 carries an Excludes2 note covering F11: “drug abuse and dependence (F11-F19)”

Excludes2 marks distinct conditions — both may be reported when both are documented.

What to review

Report both only when the documentation supports both conditions; otherwise report the one documented.

Guide: Excludes1 vs Excludes2 Check these on a claim

Why it matters

An Excludes2 note means the excluded condition is not part of the code above it, but a patient can have both. Report both when both are documented.

Source / rule

CMS ICD-10-CM tabular instructional notes

Official guidance behind these answers

Section I.A.12.b — Excludes2 · applies to: Excludes2
A type 2 Excludes note represents “Not included here.” An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
ICD-10-CM Official Guidelines FY2026

Quoted from the ICD-10-CM Official Guidelines for Coding and Reporting in effect for the release shown. The tabular notes above are the code-level instruction; these sections are the convention that says how such a note is applied. Source document (CMS PDF) · Release and checksum

Side by side

	F11Opioid related disorders	Z79.85Long-term (current) use of injectable non-insulin antidiabetic drugs
Billing status	Non-billable header Report instead: F11.10, F11.11, F11.120, F11.121, F11.122	Billable
Classification	F01-F99 — Mental, Behavioral and Neurodevelopmental Disorders (F01-F99)	Z00-Z99 — Factors Influencing Health Status and Contact with Health Services (Z00-Z99)
Definition	Opioid related disorders is a non-billable ICD-10-CM category code (F11).	Long-term (current) use of injectable non-insulin antidiabetic drugs is a billable ICD-10-CM diagnosis code (Z79.85).
Includes	—	long term (current) drug use for prophylactic purposes
Excludes2	—	long term (current) use of insulin (Z79.4) long term (current) use of oral hypoglycemic drugs (Z79.84) drug abuse and dependence (F11-F19) drug use complicating pregnancy, childbirth, and the puerperium (O99.32-)
Code also	—	any therapeutic drug level monitoring (Z51.81) any follow-up examination (Z08-Z09)

Notes are the code’s own tabular entry, quoted as published. A note that names the other code is the one the verdict above rests on.

Edit this comparison Check a whole claim

Derived from the official CMS ICD-10-CM tabular data (FY2027). A coding-rule comparison, not billing advice: payer-specific edits and medical-necessity policy are outside its scope. All data sources