84999 Unlisted chemistry procedure
Also known as: unlisted chemistry, other lab test, NOS assay
Unspecified or unlisted chemistry, toxicology, or laboratory procedure not identified by other specific chemistry CPT codes; reserved for novel assays or codes not otherwise classifiable.
In Plain Language
special lab test; other laboratory procedure
Clinical Context
Used for new or rare laboratory tests not assigned specific codes; requires detailed documentation of methodology, clinical significance, and work effort.
RVU Information
CPT 84999 does not have a physician work RVU assigned by CMS. Reimbursement for this code is determined by payer-specific fee schedules.
Billing & Documentation
Lab and pathology codes require an order from the treating provider with clinical indication. For molecular pathology and genetic testing, document the specific analytes tested and clinical rationale.
How This Code Compares
This code has a work RVU of 0.00, meaning it does not have a physician work component assigned by CMS. In the Pathology & Lab category, 94% of codes share this characteristic.
Specialties
Frequently Asked Questions
What is CPT code 84999?
CPT 84999 (Unlisted chemistry procedure) is a Pathology & Lab code. Unspecified or unlisted chemistry, toxicology, or laboratory procedure not identified by other specific chemistry CPT codes; reserved for novel assays or codes not otherwise classifiable.
Who uses CPT code 84999?
CPT 84999 is used by Clinical Pathology, Laboratory Medicine, Specialty Labs. Used for new or rare laboratory tests not assigned specific codes; requires detailed documentation of methodology, clinical significance, and work effort.
When is CPT 84999 used?
Used for new or rare laboratory tests not assigned specific codes; requires detailed documentation of methodology, clinical significance, and work effort.
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CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.