Single, Repeated, and Maintenance Ketamine Infusions for Treatment-Resistant Depression: A Randomized Controlled Trial

Summary & key facts

Researchers tested ketamine given through an IV for people whose depression did not get better with usual treatments. In a first phase, 41 people each got one low-dose ketamine infusion and one infusion of an active placebo called midazolam, and ketamine reduced depressive symptoms more at 24 hours. After symptoms came back, people were offered six ketamine infusions over two weeks, and those who improved kept getting one infusion a week for a month to see if benefits lasted.

Key facts:

• Forty-one people with treatment-resistant depression took part in the study.
• In the first comparison, each person received both ketamine and an active placebo so doctors and patients did not know which they were getting, and ketamine reduced depression scores more than the placebo at 24 hours.
• After symptoms returned, participants were given six open ketamine infusions, three times a week over two weeks.
• About 60% of people met the study's definition of response after the repeated infusions. The exact figure reported was 59%.
• On average it took about three infusions for a person to reach that response.
• People who responded did not show further reduction in depression scores during the once-weekly maintenance infusions, but their improvements were maintained while they continued weekly dosing.
• The repeated ketamine infusions showed a cumulative effect, meaning the antidepressant benefit increased as infusions were repeated.
• The study used careful monitoring and excluded people with recent drug abuse, certain medical problems, or a history of mania, so the results apply to people similar to those in the trial.

Abstract

2019; 176:401-409).

Topics

Mental Health Research Topics Treatment of Major Depression Tryptophan and brain disorders

Categories

Health Sciences Medicine Pharmacology

Tags

Alternative medicine Anesthesia Antidepressant Clinical trial Cognition Crossover study Depression (economics) Economics Hippocampus Internal medicine Ketamine Macroeconomics Major depressive disorder Mathematics Medicine Midazolam Pathology Placebo Psychiatry Randomized controlled trial Repeated measures design Sedation Statistics Treatment-resistant depression

Substances

Ketamine

Conditions & symptoms

Depression Lack of energy or motivation Sadness or low mood