Most antidepressants don't work for children and teenagers with major depression and may even be unsafe, a new study says.
But the true effectiveness and risk of serious harms such as suicidal thoughts and attempts is unclear because of the poor quality of the evidence, say the researchers.
Their comprehensive review of clinical trial evidence found that out of 14 antidepressants only one, fluoxetine - marketed as Prozac - was more effective than a placebo at relieving the symptoms of major depression in young people.
Another drug, venlafaxine, was linked to an increased risk of suicidal thoughts and attempts compared with placebo and five other antidepressants.
"The balance of risks and benefits of antidepressants for the treatment of major depression does not seem to offer a clear advantage in children and teenagers, with probably only the exception of fluoxetine," said co-author Professor Peng Xie from The First Affiliated Hospital of Chongqing Medical University in China.
"We recommend that children and adolescents taking antidepressants should be monitored closely, regardless of the antidepressant chosen, particularly at the beginning of treatment."
The researchers analysed 34 trials involving 5620 participants, noting 22 were paid for by pharmaceutical companies.
Overall quality of the evidence in the research they studied was "very low", said the authors whose study was published in The Lancet.
The authors warned that the true effectiveness and safety of the antidepressants remained unclear because of the poor design and selective reporting of the trials.
"Without access to individual-level data it is difficult to get accurate effect estimates and we can't be completely confident about the accuracy of the information contained in published and unpublished trials," said lead author Dr Andrea Cipriani at the University of Oxford.
Writing in a linked Comment, the University of Adelaide's Dr Jon Jureidini asked how many more suicidal events might have been revealed had individual patient data been available.
"The effect of misreporting is that antidepressants, possibly including fluoxetine, are likely to be more dangerous and less effective treatments than has been previously recognised," he wrote.
"So there is little reason to think that any antidepressant is better than nothing for young people."
