T78.0
Anaphylactic reaction due to food
T78.0 is a non-billable ICD-10-CM code header for anaphylactic reaction due to food. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are T78.00 Anaphylactic reaction due to unspecified food, T78.01 Anaphylactic reaction due to peanuts, T78.02 Anaphylactic reaction due to shellfish (crustaceans), T78.03 Anaphylactic reaction due to other fish and 6 more. Its coding notes include a Use additional code instruction, a Code also instruction and 3 Excludes2 entries.
7th characters
Every code below needs one of these (defined at T78).
The appropriate 7th character is to be added to each code from category T78
- Ainitial encounter
- Dsubsequent encounter
- Ssequela
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
The 7th character depends on whether the patient is in active treatment, not on who sees the patient. An aftercare Z code is not used for injury aftercare.
Use additional code
Add the listed code as a secondary code, if known.
Also from chapter/block level (1 note)
- code to identify any retained foreign body, if applicable (Z18.-)
Code also
Two codes may be needed to describe the condition. This note gives no sequencing order.
Also from chapter/block level (6 notes)
- , if applicable, place of occurrence, such as:
- highway rest stop (Y92.523)
- school (private) (public) (state) as the place of occurrence of the external cause (Y92.21-)
- service areas as the place of occurrence of the external cause (Y92.52-)
- single-family non-institutional (private) house as the place of occurrence of the external cause (Y92.01-)
- transport vehicle as the place of occurrence of the external cause (Y92.81-)
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
- complications of surgical and medical care NEC (T80-T88)
Also from chapter/block level (2 notes)
- birth trauma (P10-P15)
- obstetric trauma (O70-O71)
Inclusion terms
Conditions classified to this code.
- Anaphylactic reaction due to adverse food reaction
- Anaphylactic shock or reaction due to nonpoisonous foods
- Anaphylactoid reaction due to food
Notes
Also from chapter/block level (2 notes)
- Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
- The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.
More specific codes under T78.0 10
- T78.00Anaphylactic reaction due to unspecified food7th char needed
- T78.01Anaphylactic reaction due to peanuts7th char needed
- T78.02Anaphylactic reaction due to shellfish (crustaceans)7th char needed
- T78.03Anaphylactic reaction due to other fish7th char needed
- T78.04Anaphylactic reaction due to fruits and vegetables7th char needed
- T78.05Anaphylactic reaction due to tree nuts and seeds7th char needed
- T78.06Anaphylactic reaction due to food additives7th char needed
- T78.07Anaphylactic reaction due to milk and dairy productsHeader
- T78.08Anaphylactic reaction due to eggsHeader
- T78.09Anaphylactic reaction due to other food products7th char needed