R21
Billable codeRash and other nonspecific skin eruption
The ICD-10 code for rash and other nonspecific skin eruption is R21.
Clinical notes
Excludes1 (not coded here)
An Excludes1 note is a pure exclusion: the excluded condition and this code should never be reported together, because the two conditions cannot occur at the same time (e.g. a congenital form vs. an acquired form of the same disease).
- specified type of rash- code to condition
- vesicular eruption (R23.8)
Includes
Terms listed here further define or give examples of the conditions grouped under this code — they describe what the code covers, not a separate diagnosis.
- rash NOS
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •Confirm the excluded condition(s) listed above are not also present — Excludes1 conditions cannot be coded together with this one.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
ICD-9-CM equivalent
Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.
- 7821
Associated MS-DRGs
R21 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.
Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.
- DRG 564Other Musculoskeletal System and Connective Tissue Diagnoses with MCC
- DRG 565Other Musculoskeletal System and Connective Tissue Diagnoses with CC
- DRG 566Other Musculoskeletal System and Connective Tissue Diagnoses without CC/MCC
- DRG 606Minor Skin Disorders with MCC
- DRG 607Minor Skin Disorders without MCC