ICD-10-CM 2027
ICD-10 code for parasitism
From the official ICD-10-CM alphabetic index entry “Parasitism”. Page updated September 29, 2026.
About coding parasitism
The ICD-10-CM code for parasitism is B89 (Unspecified parasitic disease). The official index lists 2 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on B89.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC, relative weight 2.1859), DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC, relative weight 1.0235) and DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC, relative weight 0.6787), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
More specific parasitism codes (official index)
Common questions about parasitism ICD-10 codes
What is the ICD-10 code for parasitism?
- B89 — Unspecified parasitic disease. More specific codes apply when the documentation supports them: B82.9, B88.9.
What is the ICD-10 code for intestinal parasitism?
- B82.9 — Intestinal parasitism, unspecified.
What is the ICD-10 code for skin parasitism?
- B88.9 — Infestation, unspecified.
Is B89 billable?
- Yes. B89 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can B89 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict B89 as a principal diagnosis.
Is B89 a CC or MCC?
- No. B89 is neither a CC nor an MCC under MS-DRG v44.0.