Posted in Web Ketamine for treatment-resistant depression: When and where is it safe? July 28, 2025 Ketamine has been used for decades as an anesthetic, and in 2019 an inhaled version of it was approved by the FDA for treatment-resistant depression. But it is generally prescribed only when other treatments have not been effective. https://www.health.harvard.edu/blog/ketamine-for-treatment-resistant-depression-when-and-where-is-it-safe-202208092797