Skip to content

T78.2 ICD-10-CM Code: Anaphylactic shock, unspecified

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

FY 2026 Apr update / Injury, poisoning and certain other consequences of external causes (S00-T88) / Other and unspecified effects of external causes (T66-T78)

T78.2

Header CodeICD-10-CMOfficial ICD-10-CMCodebook guidance

Anaphylactic shock, unspecified

Anaphylactic shock, unspecified

CMS-HCC V28

0

0

RAF 0

CMS-HCC V24

0

0

RAF 0

ACA/HHS

0

0

RAF 0

ESRD/PACE

0

0

RAF 0

RXHCC

0

0

RAF 0

Code Trumping

Basket needed

Code Book Path

Official
T78Adverse effects, not elsewhere classified
T78.2Anaphylactic shock, unspecified

Inclusion Terms

Official
  • Allergic shock
  • Anaphylactic reaction
  • Anaphylaxis

Excludes 2

Official
  • complications of surgical and medical care NEC (T80-T88)

Related Child Codes

Official
T78.0Anaphylactic reaction due to food
T78.1Other adverse food reactions, not elsewhere classified
T78.3Angioneurotic edema
T78.4Other and unspecified allergy
T78.8Other adverse effects, not elsewhere classified

Includes

Official

ICD-10-CM does not list Includes notes for T78.2 in this effective period.

Excludes 1

Official
  • anaphylactic reaction or shock due to adverse effect of correct medicinal substance properly administered (T88.6)
  • anaphylactic reaction or shock due to adverse food reaction (T78.0-)
  • anaphylactic reaction or shock due to serum (T80.5-)

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for T78.2 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for T78.2 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for T78.2 in this effective period.

Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.

Coder workflow notes

Get the V28 RAF + MEAT cheat sheet

One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.

Free PDF. No card. Unsubscribe anytime.

What This Code Means

T78.2 is the ICD-10-CM diagnosis code for anaphylactic shock, unspecified. T78.2 sits in the ICD-10-CM chapter for injury, poisoning and certain other consequences of external causes (s00-t88), within the section covering other and unspecified effects of external causes (t66-t78).

Header codes like T78.2 cannot be reported on claims directly, they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at T78.2's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for T78.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Excludes 1, Do NOT code together

  • anaphylactic reaction or shock due to adverse effect of correct medicinal substance properly administered (T88.6)
  • anaphylactic reaction or shock due to adverse food reaction (T78.0-)
  • anaphylactic reaction or shock due to serum (T80.5-)

Child Codes

Code Hierarchy

Work T78.2 in HCC Buddy

Open T78.2 in the Code Book for the full Index-to-Tabular path, MEAT checklist, and V28 HCC mapping, or in the Encoder to code from a keyword search. Pro includes 14 days to try everything.