This study focuses on Posttraumatic Stress Disorder, a mental health condition that can develop after experiencing or witnessing a traumatic event. The purpose of the study is to investigate whether the medication hydrocortisone can reduce the severity of symptoms compared to a placebo.

Participants in the study will be given either hydrocortisone in the form of an oral tablet or a placebo. Following the initial administration of the medication, participants will be monitored over a period of time. This involves completing various questionnaires to report on their experiences and symptoms, as well as providing samples such as saliva. Additionally, some participants may use wearable devices to track their heart rate and heart rate variability, which refers to the variation in time between each heartbeat.