Q18.5 vs Q38
Q18.5 (Microstomia) compared with Q38 (Other congenital malformations of tongue, mouth and pharynx), 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. Q38 carries an Excludes1 note covering Q18.5: “microstomia (Q18.5)”
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
| Q18.5Microstomia | Q38Other congenital malformations of tongue, mouth and pharynx | |
|---|---|---|
| Billing status | Billable | Non-billable header |
| Classification | Q00-Q99 — Congenital Malformations, Deformations and Chromosomal Abnormalities (Q00-Q99) | Q00-Q99 — Congenital Malformations, Deformations and Chromosomal Abnormalities (Q00-Q99) |
| Definition | Microstomia is a billable ICD-10-CM diagnosis code (Q18.5). | Other congenital malformations of tongue, mouth and pharynx is a non-billable ICD-10-CM category code (Q38). |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources