AutoICD API

T66

Non-billable

Radiation sickness, unspecified

Radiation sickness, unspecified

This is a header/category code. For billing purposes, use a more specific child code from the list below.

Status

Non-billable / Header

Block

T66-T78

Child Codes

3

Coding Notes

Excludes 1

Codes that cannot be used together with this code (mutual exclusion)

  • birth trauma (P10-P15)
  • obstetric trauma (O70-O71)
  • specified adverse effects of radiation, such as:
  • burns (T20-T31)
  • leukemia (C91-C95)
  • radiation gastroenteritis and colitis (K52.0)
  • radiation pneumonitis (J70.0)
  • radiation related disorders of the skin and subcutaneous tissue (L55-L59)
  • sunburn (L55.-)

Use Additional Code

Additional codes that should follow this code

  • code to identify any retained foreign body, if applicable (Z18.-)

7th Character Definitions

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

Child Codes (3)

T66.XXXA

Radiation sickness, unspecified, initial encounter

BillableT66.XXXD

Radiation sickness, unspecified, subsequent encounter

BillableT66.XXXS

Radiation sickness, unspecified, sequela

Billable

Also Known As / Clinical Terms

UMLS

Frequently Asked Questions

What is ICD-10 code T66?

ICD-10-CM code T66 represents "Radiation sickness, unspecified". It is a non-billable header code — use a more specific child code for billing purposes.

Is T66 a billable code?

No, T66 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 T66.

What chapter is T66 in?

T66 is in Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (codes S00-T88).

What codes cannot be used with T66?

T66 has Excludes1 notes indicating codes that cannot be used together with it, including: birth trauma (P10-P15); obstetric trauma (O70-O71); specified adverse effects of radiation, such as:; and 6 more.

What are the subcategories under T66?

T66 has 3 child codes, including: T66.XXXA (Radiation sickness, unspecified, initial encounter), T66.XXXD (Radiation sickness, unspecified, subsequent encounter), T66.XXXS (Radiation sickness, unspecified, sequela).

Are additional codes required with T66?

Yes, when using T66 you should also code: code to identify any retained foreign body, if applicable (Z18.-).

What are the UMLS CUIs for T66?

T66 is linked to 1 UMLS Concept Unique Identifier: C2886219. 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.