Post-traumatic stress disorder (PTSD) is a mental health condition that develops following a traumatic event. This event can be either experienced directly or witnessed by an individual. The symptoms of PTSD can be distressing and may include:

1. Reliving the Trauma: People with PTSD often experience flashbacks, hallucinations, or nightmares related to the traumatic incident.
2. Avoidance: Individuals may avoid situations, people, places, or memories that remind them of the trauma.
3. Excessive Arousal: This includes increased alertness, anger, irritability, difficulty sleeping, and difficulty concentrating.
4. Intrusive Negative Thoughts or Feelings: Guilt, shame, and other distressing emotions may persist.
5. Flat Affect: Some individuals may exhibit a lack of emotional responsiveness or dissociation.
6. Physical Symptoms: Trauma settles in the nervous system and can affect the way we feel and the way our body functions.

Causes of PTSD are often linked to traumatic events such as sexual or physical assault, the death of a loved one, accidents, war, or natural disasters. Risk factors include a family history of depression and anxiety, previous traumatic experiences, and substance abuse.