Excludes1 pair
T78.2- vs T88.6-
T78.2 and T88.6 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on T78.2
anaphylactic reaction or shock due to adverse effect of correct medicinal substance properly administered (T88.6)
T78.2
Anaphylactic shock, unspecified
Not billable
- Chapter 19
- Injury, poisoning and certain other consequences of external causes
- Section
- T66-T78
Use when the record says
- Allergic shock
- Anaphylactic reaction
- Anaphylaxis
Indexed under
- Allergy, allergic › anaphylactic reaction or shock
- Allergy, allergic › shock (anaphylactic)
- Shock › anaphylactic
T88.6
Anaphylactic reaction due to adverse effect of correct drug or medicament properly administered
Not billable
- Chapter 19
- Injury, poisoning and certain other consequences of external causes
- Section
- T80-T88
Use when the record says
- Anaphylactic shock due to adverse effect of correct drug or medicament properly administered
- Anaphylactoid reaction NOS
Indexed under
- Shock › drug › due to correct substance properly administered
- Allergy, allergic › shock › due to › adverse effect of correct medicinal substance properly administered
- Shock › anaphylactic › due to drug or medicinal substance › correct substance properly administered
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027