Ketamine in treatment-resistant depression

Summary & key facts

Ketamine is a fast-acting antidepressant used for people whose depression did not improve after at least two antidepressant trials (treatment-resistant depression). Clinical trials (nearly 50 randomized studies) and Norwegian clinical experience show ketamine often reduces depressive symptoms within hours and the benefit can last for weeks, but long-term effects, side effects, and the potential for misuse are still uncertain. In Norway, an s-enantiomer nasal spray is approved and hospitals use intravenous ketamine with careful monitoring and psychotherapy.

Key facts:

• Treatment-resistant depression is defined as not responding to at least two different antidepressants.
• About 6% of Norway's population has depression at any one time, and about 18% experience a depressive disorder during their life.
• Up to 50% of people with depression do not get enough benefit from standard treatment, and about 30% later meet criteria for treatment-resistant depression.
• Almost 50 randomized clinical trials have studied ketamine for depression, making it the most researched rapid-acting antidepressant in this group.
• Ketamine often reduces depressive symptoms within hours, and the antidepressant effect can last for several weeks beyond the time the drug is in the body.
• Common acute side effects during or after ketamine include dissociative experiences (a sense of detachment), anxiety, confusion, nausea, raised heart rate and blood pressure, dizziness, and visual changes; these are usually mild and short-l
• In Norway, the s-enantiomer of ketamine is approved as a nasal spray for depression, and intravenous racemic ketamine is used experimentally in several hospitals following national protocols.
• At one Norwegian hospital (Sykehuset Østfold) more than 300 outpatients have received intravenous ketamine; the clinicians report that over half showed a substantial reduction in depressive symptoms.
• The authors report no known cases of ketamine misuse among patients after completing a treatment series in Norway, and no suicides occurred during ketamine treatment. They note two suicides among patients who were on waitlists or had been d
• Important unanswered questions include long-term effectiveness, long-term side effects, and the potential for dependence or misuse of ketamine.

Topics

Diet and metabolism studies Treatment of Major Depression Tryptophan and brain disorders

Categories

Health Sciences Medicine Pharmacology

Tags

Medicine

Substances

Ketamine

Conditions & symptoms

Depression Lack of energy or motivation Sadness or low mood