T66.XXXABillable
Radiation sickness, unspecified, initial encounter
- Chapter
- 19. Injury, poisoning and certain other consequences of external causes
- Category
- T66
- Effective date
- October 1, 2026
Related codes in category T66
Frequently asked questions
What is ICD-10 code T66.XXXA?
T66.XXXA is an ICD-10-CM diagnosis code for Radiation sickness, unspecified, initial encounter.
Is T66.XXXA a billable code?
Yes. T66.XXXA is billable and specific enough to be used on a claim.
What ICD-10-CM chapter is T66.XXXA in?
T66.XXXA falls under Chapter 19: Injury, poisoning and certain other consequences of external causes.
When did T66.XXXA become effective?
T66.XXXA has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to T66.XXXA?
T66.XXXA belongs to category T66, which includes 3 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.