Post Traumatic Stress Disorder: PTSD
Can highly sensitive people suffer from Post Traumatic Stress Disorder? HSPs exposed to prolonged, extreme and violent types of stress can get PTSD.
Post Traumatic Stress Disorder (PTSD) is an extreme version of acute stress disorder and is sometimes referred to as chronic stress disorder. It is the result of an exposure to a life threatening event or long term ordeal. People with PTSD have persistent fear symptoms long after the event has taken place.
A PTSD sufferer relives the traumatic experience or ordeal and experiences the same feelings as in the past.The reexperiencing of trauma is one of the causes of stress for PTSD sufferers. Any number of triggers can set off the memory, and result in the flashback. Hypervigilance and arousal are typical symptoms associated with this illness. 
Causes of PTSD
People who experience this disorder usually do so because of a human induced violent event. War, wartime interment, torture, and familial situations where physical, emotional, mental and sexual abuse are the experience of the victim are known causes of PTSD. These experiences affect the bond of trust between people, and when that bond is from someone in a position of authority or care, it can be a life altering experience. All of these experiences also affect the victims relationship and view of themselves in an adverse way.
Physically, a traumatic event or series of events over a long period of time can affect the brain neurology when excessive amount of adrenaline are in the body for too long, creating patterns that are then hard to break.
Not everyone with PTSD has been through a dangerous event. Some people get PTSD after a friend or family member experiences danger or is harmed. The sudden, unexpected death of a loved one can also cause PTSD. NIMH
There is some evidence that individuals including highly sensitive people can have an inherited predisposition to PTSD.
The treatment of Post Traumatic Stress Disorder seems to be more effective with behavioral and cognitive therapy methods than with medication. Desensitization and exposure therapy are often used to help reduce the sufferer's symptoms.
If you believe you are suffering from PTSD and are or were also a member of the military, you can access special PTSD information here just for you: Dealing with PTSD Symptoms from Dr. DeFoore