New figures have revealed the scale of how many Australian children are being given strong anti-psychotic medications.

The ABC has obtained data that shows more than 100,000 anti-psychotic prescriptions were written last year for Australian children.

Queensland had the highest rate of prescribing three common anti-psychotic medications – almost double the rate of some states - followed by NSW.

As recently as 2012, the Federal Government estimated more than 12,000 Australian children and young people were on anti-psychotics.

Most anti-psychotic medications have been the subject of few studies looking at long or short-term impacts on children.

They have a mix of approved usages among regulators but many are prescribed "off-label" by doctors. Few are approved for children under the age of 10.

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Some specialists are concerned the medications are being given out too freely, especially by general practitioners and paediatricians.

Sorry, this video has expired Number of kids on anti-psychotic drugs concerns doctors ( Sophie Scott )

The doctors sometimes only have limited child psychiatric experience.

Of particular concern is the use of the medications among children in foster care, where parents are not able to consent to their use.

Anti-psychotics are mainly used to treat conditions such as schizophrenia and bipolar disorder which do not often emerge until late adolescence.

However in recent years the medications have found favour in use for children with high levels of aggressive behaviour and to treat symptoms of autism.

More anti-psychotics than psychosis

The medical profession is divided on the use of anti-psychotics.

But what they can agree on is that the medications should only be prescribed when the benefits outweigh the risks.

Child psychiatrist Jon Jureidini has been a vocal critic of overprescription.

Professor Jureidini said there were far more anti-psychotics being prescribed than there were children with schizophrenia or bipolar disorder.

"We should make no mistake about these drugs – they are dangerous drugs,'' he said.

"They cause considerable weight gain and disturbances to metabolism in children who take them."

Professor Jureidini said there was no clear evidence anti-psychotics were safe among children, even in the short term.

"It's definitely experimental because it's not being based on any clear evidence of benefit or lack of harm," he said.

"There's nothing wrong with using drugs experimentally as long as you're open and honest about that."

Professor Jureidini said high prescription rates in particular states pointed to some practitioners favouring some medications and diagnoses over others.

However, he said they could equally represent the fact that some practitioners specialised in particular disorders.

He is concerned drugs are being increasingly used to treat problems that could be helped with psychology.

"I think for we doctors... unfortunately we're too much influenced by the pharmaceutical industry and their key opinion leaders," he said.

Most kids and parents do not want to be on anti-psychotics, doctor

The Royal Australian and New Zealand College of Psychiatrists said there were legitimate reasons to prescribe the medications to children.

Child and adolescent psychiatry chair Dr Nick Kowalenko said the medication helped with psychosis, which could be a symptom in a range of mental health conditions.

They also helped children with post-traumatic stress and autism.

"Sometimes we do see kids who have aggressive and behaviour problems who've had a range of many other treatments and sometimes they do benefit from anti-psychotic treatment," he said.

"And that would be off label treatment."

The medications could cause "dramatic changes" in young people with behaviour problems and aggression.

"You can imagine most kids and most parents do not want to be on those medications, especially psychotropic ones.

"Often times an adolescent will tell you yes they're experiencing a side effect, but it's better than what they had before."

Dr Kowalenko said it would be rare for the medications to be prescribed on their own and they should be given as part of a suite of treatments including counselling, parenting skills and family therapy.

"I guess that would be our main concern as child psychiatrists, that the majority of these prescriptions are provided by GPs and by paediatricians," he said.

"They should not be substitute for a comprehensive treatment approach."

'Chemical restraint' in foster care

Professor Jureidini said it was an international phenomenon that children in care were much more likely to be overprescribed anti-psychotic medication.

"You could argue that they come into foster care with a level of disturbance that warrants more psychiatric interventions, but I don't think that explains it,'' he said.

"I think we have to face up to the fact that children in foster care are being inappropriately overmedicated.

"If you give a so-called anti-psychotic medication to a child with behavioural problems that is a form of chemical restraint.

"As part of a whole behavioural management strategy you might be able to justify that chemical restraint, but my fear is it's being used much more broadly than when it's an absolute necessity."

If you or anyone you know is in need of support, contact Lifeline Australia on 13 11 14, Kids Helpline on 1800 55 1800 or visit BeyondBlue.