T78.40

The ICD-10-CM code for allergy, unspecified is T78.40. The full clinical description is "Allergy, unspecified". T78.40 is a non-billable header code. Use a more specific child code for billing purposes.

ICD-10-CM code T78.40 represents “Allergy, unspecified”. It is classified under Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes and is a non-billable header code. Use a more specific child code for billing purposes.

No, T78.40 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 T78.40.

T78.40 is in Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (codes S00-T88).

T78.40 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.

T78.40 has 3 child codes, including: T78.40XA (Allergy, unspecified, initial encounter), T78.40XD (Allergy, unspecified, subsequent encounter), T78.40XS (Allergy, unspecified, sequela).

Yes, when using T78.40, also report: any retained foreign body, if applicable (Z18.-).

T78.40 is linked to 2 UMLS Concept Unique Identifiers: C1527304, C0020517. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.

ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like allergy, unspecified affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.

There is no direct ICD-11 mapping available for T78.40 in the WHO crosswalk tables. This may mean the concept is classified differently in ICD-11. Use the ICD-10 to ICD-11 converter to search for related codes.