2020 ICD-10-CM Diagnosis Code T78.40XA

Allergy, unspecified, initial encounter

    2016 2017 2018 2019 2020 Billable/Specific Code
  • T78.40XA is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2020 edition of ICD-10-CM T78.40XA became effective on October 1, 2019.
  • This is the American ICD-10-CM version of T78.40XA - other international versions of ICD-10 T78.40XA may differ.
The following code(s) above T78.40XA contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to T78.40XA:
  • S00-T88
    2020 ICD-10-CM Range S00-T88

    Injury, poisoning and certain other consequences of external causes

    Note
    • 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
    Type 1 Excludes
    Use Additional
    • code to identify any retained foreign body, if applicable (Z18.-)
    Injury, poisoning and certain other consequences of external causes
  • T78
    ICD-10-CM Diagnosis Code T78

    Adverse effects, not elsewhere classified

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 2 Excludes
    • complications of surgical and medical care NEC (T80-T88)
    Adverse effects, not elsewhere classified
  • T78.4
    ICD-10-CM Diagnosis Code T78.4

    Other and unspecified allergy

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • specified types of allergic reaction such as:
    • allergic diarrhea (K52.29)
    • allergic gastroenteritis and colitis (K52.29)
    • dermatitis (L23-L25, L27.-)
    • food protein-induced enterocolitis syndrome (K52.21)
    • food protein-induced enteropathy (K52.22)
    • hay fever (J30.1)
    Other and unspecified allergy
  • T78.40
    ICD-10-CM Diagnosis Code T78.40

    Allergy, unspecified

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Applicable To
    • Allergic reaction NOS
    • Hypersensitivity NOS
    Allergy, unspecified
Approximate Synonyms
  • Allergic condition
  • Allergic disorder
  • Allergic disposition
  • Allergic reaction
  • Allergy
  • Hypersensitivity reaction
  • Immune hypersensitivity reaction
  • Non-celiac gluten sensitivity
  • Oral allergy syndrome
  • Pollen-food allergy
ICD-10-CM T78.40XA is grouped within Diagnostic Related Group(s) (MS-DRG v37.0):
  • 915 Allergic reactions with mcc
  • 916 Allergic reactions without mcc

Convert T78.40XA to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
ICD-10-CM Codes Adjacent To T78.40XA
T78.2 Anaphylactic shock, unspecified
T78.2XXA …… initial encounter
T78.2XXD …… subsequent encounter
T78.2XXS …… sequela
T78.3 Angioneurotic edema
T78.3XXA …… initial encounter
T78.3XXD …… subsequent encounter
T78.3XXS …… sequela
T78.4 Other and unspecified allergy
T78.40 Allergy, unspecified
T78.40XA …… initial encounter
T78.40XD …… subsequent encounter
T78.40XS …… sequela
T78.41 Arthus phenomenon
T78.41XA …… initial encounter
T78.41XD …… subsequent encounter
T78.41XS …… sequela
T78.49 Other allergy
T78.49XA …… initial encounter
T78.49XD …… subsequent encounter
T78.49XS …… sequela

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.