Xanax was the benzodiazepine which saw the biggest rise — its use among young people needing treatment rose almost seven-fold, from eight people to 53.
Overall, two thirds of the young people seeking help for substance abuse were male, while three-quarters were between 15 and 19, PHE said.
But their report also found a disparity between genders, with girls more likely than boys to disclose a mental health issue.
While 37% of girls starting treatment for substance addiction reported a mental health issue, only 22% of boys did.
The two reports highlight a worrying trend of rising anxiety and mental health issues among British children and adolescents, which has been highlighted by various studies in recent months.
Last month, an NHS Digital survey found that one in eight people under the age of 19
in England have a mental health issue, with the ratio rising to one in six for 17-19 year olds.
‘Far too difficult to get support’
“Young people today face huge pressures, from school stress and worries about future job and housing prospects, to the 24/7 world of social media which can exacerbate anxieties about body image or living the ‘perfect lifestyle,'” Tom Madders, director of campaigns at UK charity Young Minds, said in response to the findings.
“To make matters worse, when young people take the brave step to reach out for help, it’s far too difficult to get support,” he told CNN. “Many parents tell us that their children couldn’t access any mental health help until they were in crisis.”
Madders called for increased funding for child and adolescent mental health services to tackle the problem, adding: “We also need to fill the black hole in youth and community services that could provide help early on.”
“There’s clearly a lot of anxiety to be seen among our children and young people, and those rates are rising through childhood.”
While calls relating to anxiety and suicidal thoughts rose, the total number of calls received by Childline fell slightly from the previous year. The charity also offers help on a variety of issues, including bullying, abuse and family separation.
The hotline provided 278,440 telephone counseling sessions in the past year, down from 295,202 last year, with around two in five relating to emotional and mental health.
“We have to accept that we live in a world that makes people anxious,” Dr. Louise Theodosiou from the Royal College of Psychiatrists told CNN.
“Children themselves are accessing news that is going to contain information about the key themes that are worrying us all — global warming, pollution, Brexit,” she added. “We can understand why children might be feeling more anxious.”
“A large cohort of people who continue to have mental health problems in adulthood have them because they struggled with those problems from childhood. What we want is for people to be entering adult life healthy.”
According to the UK government, 4,500 people take their own lives in England each year, with suicide the leading cause of death in men under 45 in the country.
“As a system, we need to be working seamlessly” to tackle mental health problems, Theodosiou added. “We need to be recognizing children’s mental health needs, and we need to be providing them with clear signposts for how they can be accessing help.”