The parents, who lost their sons in Tuesday's massacre at Army Public School, were most likely to develop psychological problems, said a known psychiatrist.
"Not only parents but students elsewhere in the country, especially in Peshawar, are prone to develop post traumatic stress disorder, anxiety disorder, panic disorder, mixed anxiety depression disorder and depression," consultant psychiatrist Dr Mian Iftikhar Hussain told Dawn on Thursday.
He said that women were the worst victims of the tragedy and it was extremely difficult for them to forget their beloved ones. Thousands of students, who witnessed the bloody scene, wouldn't remain unharmed, he said.
The psychiatrist said that it would also cause depression among the members of the affected families and their friends.
It would adversely affect all fabrics of life including social, productive and physical growth due to severe distress and would ultimately lead to brain and economical drainage from the country, he added.
Dr Iftikhar said that trust in the state for protection would be further weakened and feelings of helplessness and hopelessness would further aggravate.
"From childhood to adolescence, a child passes through dramatic changes in mental health. During the transition, children gain their identity, grow physically and establish social interaction and relationship in home, in community and in society but such tragedies always affect them adversely," he said.
As the genocide of innocent young school children by the terrorists has plunged the whole nation in collective grief and mourning, its after-effects will continue to haunt people in future.
"This unmatched human tragedy will have immediate, short and long term psychological impacts on the classmates of the deceased children, their families, friends and general masses," the psychiatrist said.
Dr Iftikhar said that the immediate reaction was of severe grief at all levels, feelings of depersonalisation and derealisation. It will follow signs and symptoms of post traumatic stress disorder.
"There will be severe anxiety both among school going children and their parents that will cause marked phobias associated with schools rather than a pleasant feelings of motivation, achievements and delightfulness," he said.
Dr Iftikhar said that it would adversely affect the interest and pick up of studies in children besides their mental and social growth.
"The incident wherein about 148 persons, mostly children, were killed will disrupt all the academic and social development of children from childhood to adolescence in the long run and will have life-long bereavement among the parents and siblings of the children killed in the attack, he said.
However, the psychiatrist said that still there was a hope if they created unity among their ranks at the national level.
He said that it was a welcome sign that all political parties and all organs of establishment stood united against the terrorism in all forms.
"There will be a need of rehabilitation of the affected children of Army Public School and all students in general of other schools," Dr Iftikhar said and suggested holding orientation classes, workshops about prevention and protective measures against such events in future and reviewing the present mechanism of checking at checkpoints on the main roads.
The psychiatrist said that proper campaigns should be carried out to remove any confusion about terrorism. "Immediate counselling of the grief-stricken families is required while the students in other schools always be given lectures to save them from psychological effects in future," he said.