T78.2XXA — Anaphylactic shock, unspecified, initial encounter

T78.2XXA

ICD-10 Chapter 19: Injury & Poisoning — illustrative image — Chapter 19: Injury, poisoning and certain other consequences of external causes (S00–T88) — illustrative image

What this code means

Anaphylactic shock is a severe, whole-body allergic reaction with falling blood pressure and breathing difficulty; cause unspecified, first encounter.

Also called: anaphylactic shock, anaphylaxis.

When this code is used

Used for anaphylactic shock, unspecified, initial encounter.

Where it sits in ICD-10-CM

Code T78.2XXA belongs to Chapter 19: Injury, poisoning and certain other consequences of external causes, which covers codes S00–T88 in the FY2027 ICD-10-CM tabular list. The official description above is copied verbatim from the CDC/NCHS FY2027 code file.

Related symptoms

Breathlessness

Watch: related videos

▶ WatchAnaphylactic shock ▶ WatchAnaphylactic shock in a child peanut allergy ▶ WatchAnaphylaxis due to drug allergy

Frequently asked questions

What is ICD-10-CM code T78.2XXA?

T78.2XXA is the ICD-10-CM diagnosis code for “Anaphylactic shock, unspecified, initial encounter”. Anaphylactic shock is a severe, whole-body allergic reaction with falling blood pressure and breathing difficulty; cause unspecified, first encounter.

When is code T78.2XXA used?

Used for anaphylactic shock, unspecified, initial encounter. It belongs to Chapter 19 of ICD-10-CM (Injury, poisoning and certain other consequences of external causes).

This guide explains ICD-10-CM codes in plain language for patients, students and other readers. It is educational information only — not coding, billing or medical advice. The code recorded for any real encounter is assigned from the full clinical documentation by the treating team and qualified coders, and only they can decide which code fits a specific case.