Ketamine may reduce suicidal thoughts: Study

New York: Addictive party drug ketamine may be effective in reducing suicidal thoughts in depressed people, a study claims.

Researchers found that administration of low-dose ketamine reduced anti-suicidal thoughts within hours.

"There is a critical window in which depressed patients who are suicidal need rapid relief to prevent self-harm," said Michael Grunebaum from the Columbia University Medical Center in the US.

"Currently available antidepressants can be effective in reducing suicidal thoughts in patients with depression, but they can take weeks to have an effect," Grunebaum said.

"Suicidal, depressed patients need treatments that are rapidly effective in reducing suicidal thoughts when they are at highest risk. Currently, there is no such treatment for rapid relief of suicidal thoughts in depressed patients," Grunebaum said.

Most antidepressant trials have excluded patients with suicidal thoughts and behaviour, limiting data on the effectiveness of antidepressants in this population.

However, previous studies have shown that low doses of ketamine, an anesthetic drug, causes a rapid reduction in depression symptoms and may be accompanied by a decrease in suicidal thoughts.

For the study published in the American Journal of Psychiatry, 80 depressed adults with clinically significant suicidal thoughts were randomly assigned to receive an infusion of low-dose ketamine or midazolam, a sedative.

Within 24 hours, the ketamine group had a clinically significant reduction in suicidal thoughts that was greater than with the midazolam group.

The improvement in suicidal thoughts and depression in the ketamine group appeared to persist for up to six weeks.

Those in the ketamine group also had greater improvement in overall mood, depression, and fatigue compared with the midazolam group.

Ketamine's effect on depression accounted for about one- third of its effect on suicidal thoughts, suggesting the treatment has a specific anti-suicidal effect.

"This study shows that ketamine offers promise as a rapidly acting treatment for reducing suicidal thoughts in patients with depression," said Grunebaum.