ICD-10 Code F03.B18 – Unspecified dementia, moderate, with other behavioral disturbance (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F03.B18 – Unspecified dementia, moderate, with other behavioral disturbance
What it is
This code identifies dementia with moderate severity when the type is not specified and the patient has behavioral symptoms other than those named elsewhere in the classification. Use it when the record supports dementia but does not name a specific cause.
Clinical signs
Typical findings include clear cognitive decline affecting daily function, with moderate impairment in memory, reasoning, or orientation. Behavioral disturbance may include agitation, wandering, irritability, or other disruptive behaviors; clinical features vary, so refer to documentation.
When to use this code
Use this code when the provider documents unspecified dementia, moderate stage, and notes an additional behavioral disturbance. It is appropriate when the chart does not identify a more specific dementia type, such as Alzheimer disease or vascular dementia. Confirm that the behavior is documented and linked to the dementia diagnosis.
Do not use for
Do not use this code if the dementia type is specified and a more precise code is available. Also avoid it when behavioral symptoms are absent, not documented, or better explained by another condition; check documentation.
Coding tip
Verify both the dementia severity and the behavioral disturbance before assigning F03.B18.