R50

ICD-10Non-billable category

Fever of other and unknown origin

Official ICD-10-CM descriptor (FY2026)

Fever of other and unknown origin

R50 is a category heading, not a billable code. CMS does not accept it on a claim; report one of the more specific codes beneath it.

Excludes1

Not coded here. An Excludes1 code should never be reported at the same time as the code above it.

  • chills without fever (R68.83)
  • febrile convulsions (R56.0-)
  • fever of unknown origin during labor (O75.2)
  • fever of unknown origin in newborn (P81.9)
  • hypothermia due to illness (R68.0)
  • malignant hyperthermia due to anesthesia (T88.3)
  • puerperal pyrexia NOS (O86.4)

More specific codes under R50

Where this code sits

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Source

ICD-10-CM FY2026. Centers for Medicare & Medicaid Services (CMS) / National Center for Health Statistics (NCHS), “2026 ICD-10-CM Code Descriptions in Tabular Order (icd10cm_order_2026.txt). Download the original file from cms.gov. Public domain (US Government work). Descriptors, billable flags and instructional notes on this page are reproduced from that file without modification. Krasyn adds no clinical guidance.

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