T78.4
Non-billableOther and unspecified allergy
Other and unspecified allergy
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
- birth trauma (P10-P15)
- obstetric trauma (O70-O71)
- 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)
Excludes 2
Conditions not included here, but the patient may have both
- complications of surgical and medical care NEC (T80-T88)
Use Additional Code
Additional codes that should follow this code
- code to identify any retained foreign body, if applicable (Z18.-)
Child Codes (3)
Also Known As / Clinical Terms
Frequently Asked Questions
What is ICD-10 code T78.4?
ICD-10-CM code T78.4 represents "Other and unspecified allergy". It is a non-billable header code — use a more specific child code for billing purposes.
Is T78.4 a billable code?
No, T78.4 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 3 child codes under T78.4.
What chapter is T78.4 in?
T78.4 is in Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (codes S00-T88).
What codes cannot be used with T78.4?
T78.4 has Excludes1 notes indicating codes that cannot be used together with it, including: birth trauma (P10-P15); obstetric trauma (O70-O71); specified types of allergic reaction such as:; and 6 more.
What are the subcategories under T78.4?
T78.4 has 3 child codes, including: T78.40 (Allergy, unspecified), T78.41 (Arthus phenomenon), T78.49 (Other allergy).
Are additional codes required with T78.4?
Yes, when using T78.4 you should also code: code to identify any retained foreign body, if applicable (Z18.-).
What are the UMLS CUIs for T78.4?
T78.4 is linked to 1 UMLS Concept Unique Identifier: C2886707. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.