Ketamine reduces suicidal thoughts in depression patients

A low dose of ketamine, an anaesthetic drug which is more effective than a commonly used sedative, may be significantly effective for reducing suicidal thoughts in patients with depression, a study has recently revealed.

Columbia University Medical Center (CUMC) researchers found that ketamine's anti-suicidal effects occurred within hours after its administration.

The results suggested that ketamine's effect on depression accounted for approximately one-third of its effect on suicidal thoughts, suggesting the treatment has a specific anti-suicidal effect.

Side effects, mainly dissociation (feeling spacey) and an increase in blood pressure during the infusion, were mild to moderate and typically resolved within minutes to hours after receiving ketamine.

Lead author Michael Grunebaum said there is a critical window in which depressed patients who are suicidal need rapid relief to prevent self-harm.

"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 added.

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

The team analysed 80 depressed adults with clinically significant suicidal thoughts and were randomly assigned to receive an infusion of low-dose ketamine or midazolam, a sedative.

The findings indicated that 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.

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

Additional research to evaluate ketamine's antidepressant and anti-suicidal effects may pave the way for the development of new antidepressant medications, the researchers stated.

The research appears online in the American Journal of Psychiatry.