ICD-10 Code F02.C – Dementia in other diseases classified elsewhere, severe (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F02.C – Dementia in other diseases classified elsewhere, severe
What it is
This code identifies severe dementia caused by another underlying disease, rather than a primary dementia disorder. Use it when the record clearly links the dementia to a separate condition.
Clinical signs
Severe dementia typically includes major impairment in memory, reasoning, and daily functioning. Clinical features vary; refer to documentation for the underlying disease and the level of cognitive decline.
When to use this code
Use F02.C when the provider documents severe dementia secondary to another disease, such as a neurologic or systemic condition. The chart should support both the dementia diagnosis and the causal relationship. Check documentation if severity or cause is unclear.
Do not use for
Do not use this code for dementia without an identified underlying disease, or when the record describes only mild or unspecified severity. Check documentation if the cause is not established.
Coding tip
Always code the underlying disease first when sequencing rules apply, and confirm that “severe” is explicitly documented.