Ketamine may help some suicidal patients in the short term

Ketamine is an anaesthetic used by doctors and veterinarians, and also an illegal recreational drug. It can cause effects ranging from a user feeling happy and relaxed, and detached from their body, to vomiting, increased blood pressure and lower sensitivity to pain, depending on the dosage taken.

Researchers in France tested the drug in intravenous form  – as opposed to powder or pill form – on people with suicidal ideation on a double-blind, randomised placebo controlled trial.

Their objective was to “confirm the rapid onset anti-suicidal benefits of ketamine in the short term and at six weeks, overall and according to diagnostic group.”

The researchers write that around 700,000 people worldwide die by suicide every year, and 10 to 20 times this number attempt to end their lives (but don’t succeed). Suicide, they say, is the second most important cause of death in adolescents and young adults (after accidents).

While most suicidal ideas will not lead to a suicidal act, the authors point out, all suicidal acts are preceded by suicidal ideas. “Thus rapid resolution of a suicidal crisis before it is acted on might prevent many deaths,” they say, adding that “reducing the intensity of the suicidal pain could facilitate psychosocial intervention.”

The authors write that ketamine has been in use for the treatment of depression already, and that they wanted to test the efficacy of the drug in reducing suicidal ideation.

The patients in the trial were pooled into three diagnostic groups: bipolar disorder, depressive disorder, or other psychiatric disorders.

The study split the volunteers, consenting adults over the age of 18, into two groups: one group (73 adults) received saline solution in an IV as the control group. The other group (83 adults) received ketamine (with the dosage of 0.5 mg/kg) intravenously.

The subjects received 40 minute infusions in addition to their regular treatment at the start, and also at 24 hours.

On day 3, overall wellbeing of people who had taken the saline solution (placebo) was 31.6 percent, while the ketamine group was at 63 percent. The authors write that the study confirms in a large randomised controlled trial that “ketamine is a fast acting, efficient treatment of suicidal ideation.”

They note that the drug was tolerated well by most of the participants, with the main side effects – including sedation, depersonalisation/derealisation, nausea, and dizziness – lasting for a short period and happening to about 10 percent or fewer participants.

The ketamine effect, the researchers write, persisted “at six weeks in 69.5 percent of individuals treated with ketamine (versus 56.3 percent in those receiving placebo).” In an editorial linked to the study, psychiatry specialist Riccardo De Giorgi notes that the ketamine effect “became non-significant by week six owing to good improvement in both [the placebo and the ketamine] groups.”

Bipolar patients benefited the most

The news release notes that the results suggest “some patients with severe suicidal ideation, particularly those with bipolar disorder, could benefit from ketamine.”

At day 3, the subjects with bipolar disorder had 28.0 percent remission of suicidal ideas in the control group (saline solution placebo). However, on the same day, the subjects with bipolar disorder who were receiving ketamine had 84.6 percent remission of suicidal ideas. The researchers believe this is a remarkable difference.

The researchers determined remission on day three as scoring 3 or less total out of 38 points on a 19-question survey (Beck Scale for Suicide Ideation), with answers ranging from zero to two points per question.

They write: “A strong effect of ketamine versus placebo was found in the group with bipolar disorder, whereas the effect was moderate and did not quite reach significance in the group with “other psychiatric disorders,” and was non-significant in major depressive disorders.”

The authors also mention a participant dying by suicide over the six week period. They write that during the trial, 8.2 percent of patients in the ketamine arm and 9.8 percent in the placebo arm attempted suicide.

They note that the study was not “designed to assess the benefits of ketamine for prevention of a suicidal act, and larger studies and meta-analyses will be necessary.” The researchers also caution that the resolution of a suicidal crisis “necessitates more than medication alone. Psychological, social, and family care and support should always be combined with pharmacotherapy.”