Surge in Kiwi teens taking antidepressants, study shows

There has been an increase in the number of New Zealand children being prescribed medicine. Photo / File

The number of New Zealand teens taking a prescribed antidepressant has increased by 50 per cent over five years.

A University of Otago and the Best Practice Advocacy Centre (BPAC) study looked into the pharmaceutical use of 1.4 million New Zealand children in a bid to identify trends and areas with inappropriate prescribing.

The research collected data from 2010 and 2015 and found that prescriptions of fluoxetine - an antidepressant - increased by 50 per cent in children over 12 across the five-year period.

"We can't say why, but it is possible that depressive illness in children is being better picked up and prescriber confidence and experience with fluoxetine has increased," said David Woods, professional practice fellow at the University's School of Pharmacy.

Lead author Andrew Tomlin, of BPAC, said the research was important to identify patterns of usage in relation to educational strategies, concerns over potential excessive use, requirement for practitioner education, and for making comparisons with international trends.

Tomlin said it also provided reassurance that there were several strategies in place to monitor the use of medicines in New Zealand.

"Rather than raise undue concerns about the use of medicines in children in New Zealand, the results have identified areas where practitioner response to education and best practice recommendations appears good," Tomlin said.

Overall, the number of children using any medicine increased from 69.7 per cent in 2010 to 73.1 per cent in 2015.

The average number of prescriptions per child, per year, was 4.5 with prescription rates highest for those under two.

The most widely used medicines were antibiotics, pain-relief drugs related to the nervous system, dermatologicals and respiratory medicine.

Not surprisingly, the most common drug prescribed to children was paracetamol.

The use of methylphenidate to treat attention-deficit disorder, mainly in children older than six, increased by 37.7 per cent.

Of potential concern was the overall increase in the prescribing of the opioids codeine and tramadol, the latter of which has potential for unintentional overdose.

Recent research has advised against the use of codeine and tramadol in children.

On the other hand, the prevalence and use of systemic and topical antibiotics decreased by 2 and 10 per cent respectively.

"It is accepted that antibiotics in general are over-used and in many cases unnecessary. Our findings may reflect increased awareness of this and evidence–based prescriber education strategies that were instituted during the study period, such as restricting the use of antibiotics for ear and skin infections," Woods said.

The researchers urged medicines used by children to be monitored on a regular basis in order to evaluate which therapies are effective and which may have harmful consequences.

"This study is, in fact, a building block for the development of the techniques of data analytics to monitor the safe and effective use of medicines in all populations," Woods said.