ICD-10 Code B89 – Unspecified parasitic disease (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B89 – Unspecified parasitic disease
What it is
B89 is used when a parasitic infection is documented, but the organism or exact disease is not identified. It signals a parasitic condition without enough detail for a more specific code.
Clinical signs
Clinical features vary; refer to documentation. Patients may have nonspecific findings such as gastrointestinal complaints, skin changes, or systemic symptoms, but the record should support a parasitic infection.
When to use this code
Use B89 when the provider documents parasitic disease or infestation and does not name the parasite or specific condition. It is appropriate after evaluation when the diagnosis remains nonspecific. If later documentation identifies the organism, you should code the more specific diagnosis instead.
Do not use for
Do not use B89 when the parasite is identified or when the condition is better described by a specific infection code. Check documentation for nonparasitic causes of the symptoms.
Coding tip
Query the provider if the note says “parasitic infection” but gives no organism, site, or type.