W88 vs Y84.2
W88 (Exposure to ionizing radiation) compared with Y84.2 (Radiological procedure and radiotherapy as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure), 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. W88 carries an Excludes1 note covering Y84.2: “radiological procedure and radiotherapy (Y84.2)”
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
| W88Exposure to ionizing radiation | Y84.2Radiological procedure and radiotherapy as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure | |
|---|---|---|
| Billing status | Non-billable header Report instead: W88.0XXA, W88.0XXD, W88.0XXS, W88.1XXA, W88.1XXD | Billable |
| Classification | V00-Y99 — External Causes of Morbidity (V00-Y99) | V00-Y99 — External Causes of Morbidity (V00-Y99) |
| Definition | Exposure to ionizing radiation is a non-billable ICD-10-CM category code (W88). | Radiological procedure and radiotherapy as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure is a billable ICD-10-CM diagnosis code (Y84.2). |
| 7th character | The appropriate 7th character is to be added to each code from category W88 | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources