Could a painkiller turn people away from suicide? A preliminary trial of an opioid called buprenorphine shows that the drug can reduce suicidal thoughts after just one week. If validated in larger studies, it could become the first fast-acting anti-suicide drug.
Such a drug is sorely needed. More than 9 million adults in the US reported having suicidal thoughts in 2013. Over a million went on to attempt suicide. “Around 400,000 suicidal people are coming to emergency rooms every year,” says Elizabeth Ballard at the National Institute of Mental Health. “Pharmacologically, nothing has been approved for acute treatment of suicidal ideation, so anything that can help them is greatly needed.”
When people seek help, they may be offered behavioural therapy or drugs such as antidepressants. But neither is guaranteed to alleviate feelings, and they can take six weeks or more to kick in. Ketamine is being considered as an immediate treatment, but the drug can cause hallucinations and its effects wear off quickly. “Having something you could use on your own outside of a hospital would be beneficial,” says Ballard.
Jaak Panksepp at Washington State University in Pullman and his colleagues decided to test whether an opioid can counter suicidal feelings. Opioids are one of the brain’s natural feel-good chemicals. They are released to relieve pain when we hurt ourselves, and are involved when we deal with mental pain, such as that caused by social rejection, a contributor to suicidal thoughts.
Recent studies have shown that the system seems to malfunction in people with depression. Separate work has shown that giving people low doses of opioids decreases their perception of social rejection. “Converging lines of evidence point to a connection between mental pain, depression, suicidal ideation and the body’s natural opioids,” says Panksepp.
Panksepp’s team and his collaborators at the University of Haifa in Israel gave very low doses of buprenorphine to 40 people identified as being severely suicidal – almost two-thirds of the group had already tried to kill themselves. A second group received a placebo. The severity of the participants’ thoughts was measured via a questionnaire every week for a month by a psychiatrist. Half the participants were given their drug to take at home, the other half received it in the hospitals where they were staying for treatment.
At the start of the month-long trial, the average score of the participants was about 20. People given buprenorphine dropped an average of six points after one week and nearly 10 points by the end. Those given a placebo only dropped two points in the end. To put this in context, a score of 20 is deemed worrying enough to require hospitalising someone for their own safety. This isn’t generally the case for a score of 10.
Although some participants were so ill they were unable to complete the trial, a week after it had finished, everyone who had completed it reported no worsening of their condition (The American Journal of Psychiatry, doi.org/bb7t).
“Anything with effects even at the two-week to a month level would help a lot of people,” says Ballard. Panksepp thinks higher doses would make the effect kick in even earlier.
Upping the dose is likely to be controversial, though, especially in the US, where abuse of prescription opioids is so bad it is being called an epidemic.
An overdose of opioids can dampen a person’s breathing to lethal levels. But buprenorphine carries a low risk of this, because there’s a dose beyond which users get no additional pain-relief or high. It is even prescribed to people who are addicted to other opioids. What’s more, the daily doses in the team’s study were 30 times lower than the amount needed to create an addiction and no one reported withdrawal symptoms.
“Anything with effects even at the two-week to a month level would help a lot of people“
“I think they’re onto something. Buprenorphine acts on a number of different opioid receptors and it’s still unclear which one or ones are playing a role in the anti-suicidal effects,” says Joan Striebel, a psychiatrist with the California Department of State Hospitals. “I hope this work spurs more interest in what specific molecules could be involved in suicidal thought.”
“As a psychiatrist, I have spent the last 25 years of my life talking to people who want to kill themselves. Studying and treating the neurochemistry may help us prevent broken lives,” says co-author Yoram Yovell at the University of Haifa.