Post traumatic stress disorder occurs when someone has experienced a scary, dangerous, shocking, or otherwise, traumatizing event. It’s normal to feel fear or tension after a traumatic event. It’s a survival mechanism tied to your fight-or-flight response, and many people will recover from their initial trauma naturally. However, those who continue to experience fear or other emotions related to stress long after the traumatic moment has passed may be diagnosed with PTSD.
According to the National Institute of Mental Health, about 3.5 percent of adults in the U.S. had PTSD in the past year. About 36.6 percent of those adults experience severe PTSD.