R40.21Header code — not billable
Coma scale, eyes open
- Chapter
- 18. Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
- Category
- R40
- Effective date
- October 1, 2026
Related codes in category R40
R40Somnolence, stupor and comaR40.0SomnolenceYesR40.1StuporYesR40.2ComaR40.20Unspecified comaYesR40.211Coma scale, eyes open, neverR40.2110Coma scale, eyes open, never, unspecified timeYesR40.2111Coma scale, eyes open, never, in the fieldYesR40.2112Coma scale, eyes open, never, EMRYesR40.2113Coma scale, eyes open, never, at hospital admissionYesR40.2114Coma scale, eyes open, never, 24+hrsYesR40.212Coma scale, eyes open, to pain
Frequently asked questions
What is ICD-10 code R40.21?
R40.21 is an ICD-10-CM diagnosis code for Coma scale, eyes open.
Is R40.21 a billable code?
No. R40.21 is a category/header code, not billable on its own — use one of its more specific child codes instead.
What ICD-10-CM chapter is R40.21 in?
R40.21 falls under Chapter 18: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified.
When did R40.21 become effective?
R40.21 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to R40.21?
R40.21 belongs to category R40, which includes 12 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.