ICD-10 Code F02.C1 – Dementia in other diseases classified elsewhere, severe, with behavioral disturbance (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F02.C1 – Dementia in other diseases classified elsewhere, severe, with behavioral disturbance
What it is
This code identifies severe dementia caused by another underlying disease, with behavioral disturbance. Use it when the dementia is documented as secondary to a separate condition and the behavioral symptoms are part of the record.
Clinical signs
Clinical features vary; refer to documentation. Severe dementia usually includes major impairment in memory, reasoning, communication, and daily function, plus behavioral disturbance such as agitation, aggression, wandering, or psychotic-like behavior.
When to use this code
Use F02.C1 when the provider states dementia is due to another disease and also documents severe impairment with behavioral disturbance. Make sure the underlying cause is identified in the chart, since this code is not for primary degenerative dementia.
If the note only says dementia, check documentation for severity, behavioral symptoms, and the associated disease. Code the underlying condition separately when instructed by the record and coding guidelines.
Do not use for
Do not use this code for dementia without a documented underlying disease or without behavioral disturbance. Do not apply it when the severity is not stated or when the diagnosis is better supported by another dementia code.
Coding tip
Verify both components: the secondary cause and the documented behavioral disturbance, before assigning F02.C1.