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  6. 2024 ICD-10-CM Code T78
Version 2024
Non-Billable Code

2024 ICD-10-CM Diagnosis Code T78

Adverse effects, not elsewhere classified

ICD-10-CM Code:
T78
ICD-10 Code for:
Adverse effects, not elsewhere classified
Is Billable?
Not Valid for Submission
Code Navigator:

Code Classification

  • Injury, poisoning and certain other consequences of external causes
    (S00–T88)
    • Other and unspecified effects of external causes
      (T66-T78)
      • Adverse effects, not elsewhere classified
        (T78)

T78 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of adverse effects, not elsewhere classified. The code is not specific and is NOT valid for the year 2024 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Specific Coding Applicable to Adverse effects, not elsewhere classified

Non-specific codes like T78 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for adverse effects, not elsewhere classified:

  • T78.0 for Anaphylactic reaction due to food - NON-BILLABLE CODE

  • T78.00 for Anaphylactic reaction due to unspecified food - NON-BILLABLE CODE

  • T78.01 for Anaphylactic reaction due to peanuts - NON-BILLABLE CODE

  • T78.02 for Anaphylactic reaction due to shellfish (crustaceans) - NON-BILLABLE CODE

  • T78.03 for Anaphylactic reaction due to other fish - NON-BILLABLE CODE

  • T78.04 for Anaphylactic reaction due to fruits and vegetables - NON-BILLABLE CODE

  • T78.05 for Anaphylactic reaction due to tree nuts and seeds - NON-BILLABLE CODE

  • T78.06 for Anaphylactic reaction due to food additives - NON-BILLABLE CODE

  • T78.07 for Anaphylactic reaction due to milk and dairy products - NON-BILLABLE CODE

  • T78.08 for Anaphylactic reaction due to eggs - NON-BILLABLE CODE

  • T78.09 for Anaphylactic reaction due to other food products - NON-BILLABLE CODE

  • T78.1 for Other adverse food reactions, not elsewhere classified - NON-BILLABLE CODE

  • T78.2 for Anaphylactic shock, unspecified - NON-BILLABLE CODE

  • T78.3 for Angioneurotic edema - NON-BILLABLE CODE

  • T78.4 for Other and unspecified allergy - NON-BILLABLE CODE

  • T78.40 for Allergy, unspecified - NON-BILLABLE CODE

  • T78.41 for Arthus phenomenon - NON-BILLABLE CODE

  • T78.49 for Other allergy - NON-BILLABLE CODE

  • T78.8 for Other adverse effects, not elsewhere classified - NON-BILLABLE CODE

Coding Guidelines

The appropriate 7th character is to be added to each code from block Adverse effects, not elsewhere classified (T78). Use the following options for the aplicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Type 2 Excludes

Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
  • complications of surgical and medical care NEC T80 T88

7th Character Note

7th Character Note
Certain ICD-10-CM categories have applicable 7th characters. The applicable 7th character is required for all codes within the category, or as the notes in the Tabular List instruct. The 7th character must always be the 7th character in the data field. If a code that requires a 7th character is not 6 characters, a placeholder X must be used to fill in the empty characters.
  • The appropriate 7th character is to be added to each code from category T78

7th Character

7th Character
Indicates that a seventh character is to be assigned to codes in a subcategory.
  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.