If suicide is the question, could ketamine be the answer? Nick Clegg has suggested suicide is avoidable in a well-structured NHS, but targeting the right people remains a complex issue.

It’s not just about depression, as the case of a 65-year-old woman who made a shocking announcement to her doctors demonstrated. “I’m fed up with life, I’ve had enough,” she said. “I don’t want to live any more . . . I no longer wish to live, to see anything, hear anything, feel anything . . .”

This was shocking because the feelings were induced not by depression, but by electrical stimulation of the brain. It was an unexpected side effect of an experimental treatment for Parkinson’s disease.

Applying a current through electrodes implanted in the patient’s brain was meant to alleviate tremors; instead, it brought on suicidal thoughts within five seconds, and 90 seconds after turning it off they were gone. Then came roughly five minutes of euphoria and general larking about.

This remarkable finding, reported in the New England Journal of Medicine in 1999, was one of the first to suggest that suicide and depression are not as inextricably linked as we might imagine.

We have more recent data, too. Ten years have passed since we discovered a link between suicidal thoughts and the antidepressants known as selective serotonin reuptake inhibitors (SSRIs). Doctors became much more wary about prescribing SSRIs but the results were not as we’d hoped.

A Swedish study found that after warnings about SSRIs were issued in 2004, the suicide rate among ten-to-19-year-olds increased for five consecutive years – the largest group being those who were not prescribed antidepressants. In the US, child and adolescent suicide rates have risen by 14 per cent.

Two US-based researchers, Robert Gibbons and J John Mann, argue it is time to review the FDA warning. Writing in the Psychiatric Times, they point out that subsequent research has shown a complex relationship between suicide contemplation, depression and antidepressants. The result of the warning has not been a lower suicide rate. “Instead, we see fewer antidepressant prescriptions, an increase in youth suicides, and negative effects on human capital.”

The Parkinson’s patient’s experience – especially, perhaps, the euphoria and larking about – suggests that ketamine, the newest route to alleviating suicidal thoughts, might be more successful.

Most people know ketamine – if they know it at all – as a party drug. Though it was first developed as an anaesthetic, it can elicit euphoria at lower doses. We now know, thanks to a study published in the Journal of Psychiatric Research in December, that ketamine is also a useful reliever of suicidal thoughts.

By giving 133 patients a dose of ketamine, researchers teased apart the links between suicidal thoughts, depression and anxiety, and they found that, although ketamine does relieve depression and anxiety, its effect on suicidal ideation is far stronger than on either of these. The effect is rapid – some patients report their contemplation of suicide gone within a couple of hours. According to a report in Nature, many pharmaceutical companies are now accelerating their ketamine research.

There are plenty of wrinkles to iron out. How would we set the threshold of eligibility? And how much autonomy do we give people? Where people are under the care of the state, all means for suicide are removed from those deemed at risk. Would we sanction a ketamine shot – or a routine of ketamine shots – as a mandatory measure to be used along with removal of belt and shoelaces? Or for anyone deemed to be a danger to themselves? If Clegg gets his way, we may soon find out.