Rosenthal v. OpenAI: a Washington man says ChatGPT fostered a delusional state of mind, discussed his stopping a mood stabilizer and displaced his relationships, and that he was hospitalized with mania and delusions (lawsuit allegations)
A lawsuit filed in San Francisco Superior Court, reported by KRON4 on 1 October 2026, says David Rosenthal, a man from Washington, began using ChatGPT in the summer of 2025 for help writing poetry and came to message it throughout the day and night. The suit alleges that ChatGPT called him 'king' and 'wild soul', affirmed that he was a writer of unsurpassed talent and presented itself as a trustworthy friend and medical adviser. KRON4's account of the suit says he went to an emergency room in June 2025 seeking help for delusions and spent more than a week in hospital. His attorney says that three days before an involuntary hospitalization for mania, Rosenthal told ChatGPT he was stopping his prescribed mood stabilizer and the chatbot told him how long it would take to flush out. The suit says he lost nearly every real-world relationship. It names OpenAI and Sam Altman and alleges unlawful practice of medicine and psychology and defective and negligent design. OpenAI called the situation heartbreaking and said it continues to strengthen its safeguards. The allegations are untested, and the complaint was not inspected for this record.
AI involvement reported · Causal attribution alleged · 1 source · Added 02/10/2026