E73 vs R79.83
E73 (Lactose intolerance) compared with R79.83 (Abnormal findings of blood amino-acid level), 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. R79.83 carries an Excludes1 note covering E73: “specific findings indicating disorder of carbohydrate metabolism (E73-E74)”
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
| E73Lactose intolerance | R79.83Abnormal findings of blood amino-acid level | |
|---|---|---|
| Billing status | Non-billable header | Billable |
| Classification | E00-E89 — Endocrine, Nutritional and Metabolic Diseases (E00-E89) | R00-R99 — Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (R00-R99) |
| Definition | Lactose intolerance is a non-billable ICD-10-CM category code (E73). | Abnormal findings of blood amino-acid level is a billable ICD-10-CM diagnosis code (R79.83). |
| Includes | — | Homocysteinemia |
| Use additional code | — | code to identify any retained foreign body, if applicable (Z18.-) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources