Post-traumatic stress disorder (PTSD) is a debilitating, and often chronic, mental health disorder that develops after exposure to a traumatic event. PTSD affects people of all ages, and should be differentiated from acute stress disorder (ASD), which is a severe, self-limited reaction to a stressful or traumatic event.
ASD typically resolves within a month, while PTSD lasts longer for most individuals.
PTSD typically occurs after an event that poses physical harm, risk of death, and/or the actual death of a child, parent/caregiver, or loved one. This event triggers excessive anxiety, fear, stress, and depression that lasts for more than a month. 
PTSD involves four symptom clusters:
People with PTSD typically experience reoccurring flashbacks of the traumatizing event. These flashbacks can take the form of nightmares, distressing memories, and/or re-enactments during play (particularly in children).
People with PTSD tend to avoid certain situations because they remind them of the trauma they experienced.
People with PTSD tend to have distressing and/or violent fluctuations in cognition and mood.
People with PTSD typically have a hard time concentrating, are easily startled, and are regularly anxious or nervous. 
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Some children who are exposed to traumatic experiences (i.e. abuse, particularly sexual abuse, but also physical or emotional abuse, violence, natural disasters, and/or war) may exhibit signs of PTSD. Oftentimes, these symptoms are specific to the age of the child (Table 1).
For example, symptoms in a preschooler may include:
In addition, parents may notice that their children are “re-experiencing” the trauma vicariously through their toys. For example, a child may engage in “repetitive play,” the repeated re-telling of the traumatic event during playtime. It is important to understand that this may be the child’s way of coping with the trauma they endured.
More specifically, it may be their way of “working through the trauma” via play. This coping strategy helps children with PTSD understand and master both their feelings and the trauma. 
Keep in mind, children ages 6-12 may show regressive behaviors:
Teenagers, on the other hand, tend to experiences more “adult-like” symptoms of PTSD:
Table 1: Nelsons Textbook of Pediatrics
It is important to note that not every child who experiences trauma will develop PTSD. In fact, only a small number of children who are exposed to trauma go on to develop it.
For instance, a recent study indicated that fewer than 16% of children who experience a traumatic event will eventually develop PTSD.  Similarly, another recent study showed that only 10% of children develop PTSD following a traumatic experience. 
Furthermore, up to 40% of people may show symptoms of PTSD, but do not fulfill all of the diagnostic criteria. Therefore, there may be more people with PTSD who remain undiagnosed.
Although medical experts cannot predict with absolute certainty which children will develop PTSD, there are certain risk factors that predispose a child to it.
These risk factors include:
It is important to note that trauma can lead to PTSD AND other psychological conditions, such as: depression, antisocial behavior, mood disorders, and disruptive relationships/sense-of-self.
All of these conditions can be disruptive to social and emotional development, so your child should be evaluated after any traumatic event to ensure they receive an accurate diagnosis and begin receiving the support and therapy they need as soon as possible.
If, after experiencing a traumatic event, your child experiences persistent and uncontrollable thoughts or dreams, a heightened sense of fear, and/or emotional distress, ask your child’s pediatrician about getting a mental health evaluation.
It is the uncontrollable, intrusive, and distressing thoughts that set PTSD apart from other anxiety-related disorders. Therefore, it is important to be aware of these symptoms after your child experiences a stressful event, especially if the symptoms last longer than a month.
A medical doctor, psychologist, or mental health provider usually diagnoses PTSD by using the DSM-5. This diagnosis is based on a review of the child’s symptoms. It is important to note that in children 6 and younger, fewer symptoms are considered “normal” during the evaluation process. In other words, even though the criteria for children younger and older than 6 years old are similar, younger children need fewer of them to meet the criteria for PTSD.
The diagnostic criteria of PTSD include: 
These symptoms can occur with or without dissociative symptoms:
The feeling of being detached from oneself (As if one is “floating above” his/her body). Children suffering from PTSD report feeling as if they are in a dream, or that time is moving very slowly.
Children with PTSD may feel like the world around them is not real.
After a child has experienced a traumatic event, the focus should be on returning them to the parent or caregiver. This step is necessary to re-establish feelings of comfort and security. More specifically, re-establishing the child’s regular routine is of paramount importance, because it prevents them from feeling insecure and unstable.
Listed below are things that must be done to stabilize a child following a traumatic event:
There is also evidence that treating a child’s physical pain after a traumatic event may protect them from developing PTSD in the future.  Ultimately, however, the goal of treatment is to break the association between the trauma and feelings of helplessness.
After the child has been stabilized, a long-term treatment plan is usually put into place.
This treatment plan typically includes the following:
It is important to note that CBT remains the cornerstone of mental health treatment for most anxiety and mood disorders, including PTSD. This type psychotherapy usually involves individualized therapy tailored towards changing the child’s perception of themselves as a “victim,” and empowering them to view themselves as a “survivor.”
And, depending on the age of the child, this can be accomplished through play therapy (in younger children) or psychodynamic therapy (in older children).
Further reading: Prevent PTSD: 11 Things To Do If Your Child Has Been Through Trauma
As previously discussed, CBT is the gold standard in the treatment of PTSD. An individualized treatment plan, therapeutic play, child and family therapy, and a renewed sense of security can provide a child with the tools needed to effectively cope with PTSD symptoms.
In some cases, medications are used to help wrangle PTSD symptoms under control. In addition, for children who exhibit aggression, excessive startle reactions, and/or sleep disturbances, medications like clonidine or guanfacine may be needed for stabilization and maintenance.
In fact, a popular class of anti-depressants (SSRIs) can make a world of difference in children who suffer from both depression and anxiety. However, recent child and adolescent trials did not show a significant decrease in PTSD symptoms in children and adolescents who took SSRIs.
Thus, SSRIs are more likely to benefit children who have PTSD and another mental health condition (i.e. comorbid depression, anxiety disorders, or “emotional numbness”).
The outlook for PTSD depends on many factors. More specifically, approximately 75% of individuals (children and adults) completely recover from it, while approximately 33% of individuals develop chronic PTSD (with periodic relapses). The latter cases typically occur when the following risk factors are present: 
Still, according to a recent study, approximately 50% of adolescents with PTSD fully recovered 3-4 years later. 
Keep in mind that if your child has recently been diagnosed with PTSD, they may be overwhelmed and discouraged. The key is to remember that with adequate therapy, self-care, and familial support, the majority of children recover from this condition and go on to live happy and healthy lives without the threat of reoccurring PTSD symptoms.
It is also important to be realistic; it may take several years of persistent and intentional self-care for your child to fully conquer their PTSD, so continually reassure them that they are not alone. And, encourage them to rely on you, their family, friends and their doctor to cope with any triggers.
If you are able to do this for your child, you’ll be more likely to succeed in reshaping their self-image and helping them to feel empowered, valuable, and irreplaceable.