Giving your child a smartphone is like "giving them a gram of cocaine", a top addiction therapist has warned.
Time spent messaging friends on Snapchat and Instagram can be just as dangerously addictive for teenagers as drugs and alcohol, and should be treated as such, school leaders and teachers were told at an education conference in London.
Speaking alongside experts in technology addiction and adolescent development, Harley Street rehab clinic specialist Mandy Saligari said screen time was too often overlooked as a potential vehicle for addiction in young people.
"I always say to people, when you're giving your kid a tablet or a phone, you're really giving them a bottle of wine or a gram of coke," she said.
"Are you really going to leave them to knock the whole thing out on their own behind closed doors?
"Why do we pay so much less attention to those things than we do to drugs and alcohol when they work on the same brain impulses?"
Her comments follow news that children as young as 13 are being treated for digital technology - with a third of British children aged 12-15 admitting they do not have a good balance between screen time and other activities.
"When people tend to look at addiction, their eyes tend to be on the substance or thing - but really it's a pattern of behaviour that can manifest itself in a number of different ways," Ms Saligari said, naming food obsessions, self-harm and sexting as examples.
Concern has grown recently over the number of young people seen to be sending or receiving pornographic images, or accessing age inappropriate content online through their devices.
Ms Saligari, who heads the Harley Street Charter clinic in London, said around two thirds of her patients were 16-20 year-olds seeking treatment for addiction - a "dramatic increase" on ten years ago - but many of her patients were even younger.
In a recent survey of more than 1,500 teachers, around two-thirds said they were aware of pupils sharing sexual content, with as many as one in six of those involved of primary school age.
More than 2,000 children have been reported to police for crimes linked to indecent images in the past three years.
"So many of my clients are 13 and 14 year-old-girls who are involved in sexting, and describe sexting as 'completely normal'," said Ms Saligari
Many young girls in particular believe that sending a picture of themselves naked to someone on their mobile phone is "normal", and that it only becomes "wrong" when a parent or adult finds out, she added.
"If children are taught self-respect they are less likely to exploit themselves in that way," said Ms Saligari. "It's an issue of self-respect and it's an issue of identity."
Speaking alongside Ms Saligari at the Highgate Junior School conference on teenage development, Dr Richard Graham, a Consultant Psychiatrist at the Nightingale Hospital Technology Addiction Lead, said the issue was a growing area of interest for researchers, as parents report struggling to find the correct balance for their children.
Ofcom figures suggest more than four in ten parents of 12-15 year-olds find it hard to control their children's screen time.
Even three and four year olds consume an average of six and half hours of internet time per week, according to the broadcasting regulators.
Greater emphasis was needed on sleep and digital curfews at home, the experts suggested, as well as a systematic approach within schools, for example by introducing a smartphone amnesty at the beginning of the school day.
"With sixth formers and teenagers, you're going to get resistance, because to them it's like a third hand," said Ms Saligari, "but I don't think it's impossible to intervene. Schools asking pupils to spend some time away from their phone I think is great.
"If you catch [addiction] early enough, you can teach children how to self-regulate, so we're not policing them and telling them exactly what to do," she added.
"What we're saying is, here's the quiet carriage time, here's the free time - now you must learn to self-regulate. It's possible to enjoy periods of both."
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