Is T78.1 a billable ICD-10-CM code?

No. T78.1 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does T78.1 sit in the tabular list?

Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Other and unspecified effects of external causes (T66-T78).

What cannot be coded together with T78.1?

T78.1 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

T78.1

T78.1 — Other adverse food reactions, not elsewhere classified

Non-billable headerICD-10-CM

T78.1 is a non-billable header ICD-10-CM code for other adverse food reactions, not elsewhere classified. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.

This code requires a 7th character

The appropriate 7th character is to be added to each code from category T78

A: initial encounter
D: subsequent encounter
S: sequela

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

anaphylactic reaction or shock due to adverse food reaction (T78.0-)
anaphylactic reaction due to food (T78.0-)
bacterial food borne intoxications (A05.-)

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

allergic and dietetic gastroenteritis and colitis (K52.29)
allergic rhinitis due to food (J30.5)
dermatitis due to food in contact with skin (L23.6, L24.6, L25.4)
dermatitis due to ingested food (L27.2)
food protein-induced enterocolitis syndrome (K52.21)
food protein-induced enteropathy (K52.22)

Use additional code

Add a secondary code to capture the detail described below.

code to identify the type of reaction, if applicable

Other codes that can never be billed with T78.1

These codes carry an Excludes1 note pointing at T78.1. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading T78.1 alone.

T78.110Other adverse food reactions due to milk and dairy products with tolerance to baked milk
T78.110AOther adverse food reactions due to milk and dairy products with tolerance to baked milk, initial encounter
T78.110DOther adverse food reactions due to milk and dairy products with tolerance to baked milk, subsequent encounter
T78.110SOther adverse food reactions due to milk and dairy products with tolerance to baked milk, sequela
T78.111Other adverse food reaction due to milk and dairy products with reactivity to baked milk
T78.111AOther adverse food reaction due to milk and dairy products with reactivity to baked milk, initial encounter
T78.111DOther adverse food reaction due to milk and dairy products with reactivity to baked milk, subsequent encounter
T78.111SOther adverse food reaction due to milk and dairy products with reactivity to baked milk, sequela

Risk adjustment

T78.1 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead T78.1

3 child codes. Green means billable.

Related codes at this level

Codes that share T78. If T78.1 is not quite right, the correct code is usually one of these.

Questions about T78.1

Is T78.1 a billable ICD-10-CM code?: No. T78.1 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does T78.1 sit in the tabular list?: Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Other and unspecified effects of external causes (T66-T78).
What cannot be coded together with T78.1?: T78.1 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.