T49.8X3A (Poisoning by other topical agents, assault, initial encounter) compared with T49.8X3D (Poisoning by other topical agents, assault, subsequent encounter), from the official CMS tabular data. T49.8X3A and T49.8X3D code the same injury at a different phase of treatment.
Same underlying diagnosis, different encounter phase.
The 7th character records the phase of care for the encounter being coded, so a single encounter takes one of these characters, not several. Review whether both phases belong on the same episode of care.
Source: ICD-10-CM Official Guidelines, Section I.C.19.a
Same injury, other encounter phase. T49.8X3A and T49.8X3D code the same injury at a different phase of treatment, set by the 7th character.
The 7th character records the type of care given at the encounter being coded (ICD-10-CM Official Guidelines, Section I.C.19.a), so one encounter takes one of these, not both.
| T49.8X3APoisoning by other topical agents, assault, initial encounter | T49.8X3DPoisoning by other topical agents, assault, subsequent encounter | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) |
| Definition | Poisoning by other topical agents, assault, initial encounter is a billable ICD-10-CM diagnosis code (T49.8X3A). | Poisoning by other topical agents, assault, subsequent encounter is a billable ICD-10-CM diagnosis code (T49.8X3D). |
| 7th character | The appropriate 7th character is to be added to each code from category T49 | The appropriate 7th character is to be added to each code from category T49 |
| Includes | poisoning by, adverse effect of and underdosing of glucocorticoids, topically used adverse effect of correct substance properly administered poisoning by overdose of substance poisoning by wrong substance given or taken in error | poisoning by, adverse effect of and underdosing of glucocorticoids, topically used adverse effect of correct substance properly administered poisoning by overdose of substance poisoning by wrong substance given or taken in error |
| Use additional code | code(s) to specify: manifestations of poisoning underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9) | code(s) to specify: manifestations of poisoning underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9) |
| Code first | , for adverse effects, the nature of the adverse effect, such as: adverse effect NOS (T88.7) | , for adverse effects, the nature of the adverse effect, such as: adverse effect NOS (T88.7) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources