Ketamine in Bipolar Disorder: A Review

Summary & key facts

This paper reviews what is known about using ketamine to treat bipolar disorder. The authors looked at many studies and found that ketamine can lift depression and reduce suicidal thoughts very quickly in some people. Most evidence comes from people with ordinary (unipolar) depression, not bipolar illness, so the data for bipolar disorder are much smaller. Early results are promising, but we do not yet know how safe or lasting the benefits are for people with bipolar disorder. More and better studies are needed before ketamine can be considered a routine treatment for bipolar depression.

Key facts:

• Bipolar disorder affects more than 1% of people and has one of the highest lifetime risks of suicide among psychiatric illnesses.
• The authors reviewed clinical studies and found that a single low-dose intravenous ketamine infusion often produced a fast antidepressant effect in people with bipolar depression in small controlled trials.
• In one open study of 42 people with bipolar depression, about half (52%) responded to a single ketamine infusion.
• When several low-dose ketamine infusions were given over days or weeks, some small studies reported higher response rates: one study of 16 bipolar patients found about 75% responded and about 63% reached remission after six infusions.
• Ketamine also showed rapid reductions in suicidal thoughts. Reviews and meta-analyses found decreases in suicidal thinking within one day, and some evidence of change as early as about four hours after a single infusion.
• Across research, side effects were generally mild and short-lived in the studies reviewed, but long-term safety and effects on future mood episodes are not well known.
• Most ketamine research in psychiatry focuses on ordinary (unipolar) depression. Of roughly 140 registered ketamine trials, only a very small share include people with bipolar disorder, so evidence specific to bipolar illness is limited.
• It is not yet clear whether ketamine increases the chance of switching from depression into mania in bipolar patients. Some studies reported brief mood elevations in about 7–10% of people, but these returned to baseline quickly.

Abstract

Bipolar disorder (BD) is a psychiatric illness associated with high morbidity, mortality and suicide rate. It has neuroprogressive course and a high rate of treatment resistance. Hence, there is an unquestionable need for new BD treatment strategies. Ketamine appears to have rapid antidepressive and antisuicidal effects. Since most of the available studies concern unipolar depression, here we present a novel insight arguing that ketamine might be a promising treatment for bipolar disorder.

Topics

Bipolar Disorder and Treatment Treatment of Major Depression Tryptophan and brain disorders

Categories

Health Sciences Medicine Pharmacology

Tags

Bipolar disorder Cognition Depression (economics) Economics Ketamine Lithium (medication) Macroeconomics Major depressive disorder Medical emergency Medicine Poison control Psychiatry Suicide prevention Suicide rates Treatment-resistant depression

Substances

Ketamine

Conditions & symptoms

Depression Anxiety or worry Lack of energy or motivation Poor sleep Sadness or low mood