For thousands of teenagers, the nightmares of the exam room and results day are now over. There should be a little bit of summer left to celebrate, but for some individuals, the stresses of studying and securing a place at university will have triggered or contributed to a low mood, even depressive illness.

Talking therapies can be worth trying. Antidepressants are an option, too, but when it comes to prescribing them for this age group, there is a long and controversial history to consider.

In 2003, GlaxoSmithKline wrote a memo to all UK GPs informing them that trial results for the antidepressant paroxetine had shown unacceptably high levels of side effects in patients under the age of 18. In particular, the letter warned that the drug seemed to prompt suicidal feelings.

Paroxetine was one of the selective serotonin re-uptake inhibitor (SSRI) class of drugs that had been a welcome advance on the older tricyclic type of antidepressants, which could have unpleasant side effects. Soon after Glaxo’s letter, other SSRIs were given similar warnings. Later that year, the Medicines and Healthcare Regulatory Authority, which licenses prescription medicines in the UK, banned the use of all but one SSRI antidepressant for under-18s. The exception was fluoxetine, better known as Prozac.

This was followed by warnings from the US Food and Drug Administration, not just for under-18s, but also for under-25s. Awareness of these problems has been heightened by recent republication of the FDA’s data in the British Medical Journal. The analysis of 372 double blind, randomised placebo-controlled trials concluded that “Risk of suicidality associated with use of antidepressants is strongly age-dependent”.

Should young people avoid antidepressants altogether? One has to ask how much benefit there is in the first place. In 2004, an analysis of several trials of antidepressants in young people concluded that “in discussing their own data, the authors of all of the four larger studies have exaggerated the benefits, downplayed the harms, or both”.

The authors of a 2007 Cochrane review on the effects of SSRIs on children and adolescents expressed concern that children in trials were likely to be less ill than patients seen in clinical practice. This may mean that useful effects of SSRIs have not been properly examined in very depressed young people. These drugs might be useful for some – but who?

The medical establishment is partly to blame for the fact that such questions are still unanswered. Children and young people respond differently to treatments than adults. Clinical trials in children are less common, usually because it is difficult to obtain ethical committee approval. But surely it’s more unethical not to do the trials at all.

Margaret McCartney is a GP in Glasgow.
margaret.mccartney@ft.com

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