T80.5 vs T88.6
T80.5 and T88.6 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on T80.5
anaphylactic reaction or shock due to adverse effect of correct medicinal substance properly administered (T88.6)
T80.5
Anaphylactic reaction due to serum
Not billable
- Chapter 19
- Injury, poisoning and certain other consequences of external causes
- Section
- T80-T88
Use when the record says
- Allergic shock due to serum
- Anaphylactic shock due to serum
- Anaphylactoid reaction due to serum
- Anaphylaxis due to serum
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 (reaction) (to)
- 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