T78.089Anaphylactic reaction due to eggs, unspecified

T78.089 is the ICD-10-CM diagnosis code for anaphylactic reaction due to eggs, unspecified. It belongs to category T78 (adverse effects, not elsewhere classified), block T66-T78 (other and unspecified effects of external causes) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is a header code, so it can't be reported by itself; one of its 3 subcodes must be used instead.

Within T78.08, choose T78.089 (unspecified) only when documentation doesn't support a more specific option: egg with tolerance to baked egg (T78.080) and egg with reactivity to baked egg (T78.081).

Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.

It was added in FY2026, effective October 1, 2025.