R40.23 vs R40.2A
R40.23 (Coma scale, best motor response) compared with R40.2A (Nontraumatic coma due to underlying condition), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. R40.2A carries an Excludes1 note covering R40.23: “Glasgow coma scale, total score (R40.23.-)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| R40.23Coma scale, best motor response | R40.2ANontraumatic coma due to underlying condition | |
|---|---|---|
| Billing status | Non-billable header Report instead: R40.2310, R40.2311, R40.2312, R40.2313, R40.2314 | Billable |
| Classification | R00-R99 — Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (R00-R99) | R00-R99 — Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (R00-R99) |
| Definition | Coma scale, best motor response is a non-billable ICD-10-CM category code (R40.23). | Nontraumatic coma due to underlying condition is a billable ICD-10-CM diagnosis code (R40.2A). |
| 7th character | The following appropriate 7th character is to be added to subcategory R40.23-: | — |
| Includes | — | Secondary coma |
| Code first | any associated: fracture of skull (S02.-) | underlying condition any associated: |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources