2026 ICD-10-CM Diagnosis Code F24

Code attributes

• Non-billable/Non-specific code

Coding rules

• Specify the leaf code — the parent code (e.g. F32) is a navigational header; billing requires a leaf code (F32.0, F32.1, etc.) that matches the documented presentation.
• Document onset, course, and severity (mild / moderate / severe) plus functional impact. Payers use this combination when adjudicating medical necessity.
• Attach a validated instrument score (PHQ-9, GAD-7, PCL-5, or equivalent) at intake and at follow-up where applicable. Objective measures support code selection and continued authorization.
• Review at every visit and update if presentation changes — including remission and partial remission states.

Clinical information

F24 (folie à deux) codes shared psychotic disorder — a delusion that develops in an individual in the context of a close relationship with another person who has an established delusion. Less commonly diagnosed under DSM-5-TR, but still maintained in ICD-10-CM. Document both individuals' presentations and the relational context.