A09 vs R19.7
A09 (Infectious gastroenteritis and colitis, unspecified) compared with R19.7 (Diarrhea, unspecified), 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. A09 carries an Excludes1 note covering R19.7: “diarrhea NOS (R19.7)”
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
| A09Infectious gastroenteritis and colitis, unspecified | R19.7Diarrhea, unspecified | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | A00-B99 — Certain Infectious and Parasitic Diseases (A00-B99) | R00-R99 — Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (R00-R99) |
| Definition | Infectious gastroenteritis and colitis, unspecified is a billable ICD-10-CM diagnosis code (A09). | Diarrhea, unspecified is a billable ICD-10-CM diagnosis code (R19.7). |
| Includes | Infectious colitis NOS Infectious enteritis NOS Infectious gastroenteritis NOS | Diarrhea NOS |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources