INTRODUCTION: Ketamine is a rapidly acting general anesthetic which is globally used in surgical analgesia, as well as in the management of pain. It is also used as a recreational drug. Because of its widespread use in surgical settings, the use of this drug presents an aeromedical problemin addition, of course, to the underlying condition for which it has been used. The literature around the mechanisms and side effects of ketamine is reasonably mature, and it is possible to make fairly dependable risk management decisions about return to flying based on the information available. Accordingly, following ketamine use it is recommended that aviators be grounded for 48 h following Aviation Medical Examiner review. If review is unavailable, the aviator should be grounded for 1 wk to allow sufficient time to identify the existence of prolonged side effects, such as psychomimetic effects or cognitive changes.Boyd NL, Navathe PD. An update to aircrew grounding periods after ketamine use. Aerosp Med Hum Perform. 2021; 92(8):670-675.