A Double-Blind, Randomized, Placebo-Controlled, Dose-Frequency Study of Intravenous Ketamine in Patients With Treatment-Resistant Depression

Summary & key facts

Researchers gave a short course of intravenous ketamine to adults whose depression had not improved with at least two antidepressants. People were randomly given either ketamine or a placebo two or three times each week for up to four weeks. By day 15, both the twice-weekly and thrice-weekly ketamine schedules lowered depression scores much more than placebo, and both schedules were about the same in effect. Side effects like headache, anxiety, feeling detached from oneself, nausea, and dizziness were common but tended to be short-lived. The study was small and only measured effects over about two weeks, so it does not show how long benefits last or how this would work for people who were ex

Key facts:

• The study enrolled adults aged 18 to 64 with treatment-resistant major depression, meaning they had not responded to at least two antidepressant medications.
• A total of 67 people received study treatment and were followed in the trial.
• Ketamine was given by infusion at a dose based on body weight, 0.5 milligrams per kilogram, either twice a week or three times a week.
• By day 15, depression rating scores dropped by about 18 points in the twice-weekly ketamine group compared with about 6 points with placebo.
• By day 15, depression rating scores dropped by about 18 points in the thrice-weekly ketamine group compared with about 3 points with placebo.
• Overall, twice-weekly and thrice-weekly ketamine produced similar antidepressant effects over the 15-day main measurement period.
• Common side effects reported by at least one in five people were headache, anxiety, temporary dissociation or feeling detached, nausea, and dizziness.
• Dissociative symptoms were short-lived and tended to lessen with repeated doses.
• The trial lasted up to four weeks, and the main comparison was at about two weeks, so the study does not tell us how long the antidepressant effect lasts beyond that time.
• People with recent substance abuse, certain other psychiatric disorders, or a past nonresponse to ketamine were not included, so the results do not apply to everyone with depression.

Abstract

Twice-weekly and thrice-weekly administration of ketamine at 0.5 mg/kg similarly maintained antidepressant efficacy over 15 days.

Topics

Functional Brain Connectivity Studies Treatment of Major Depression Tryptophan and brain disorders

Categories

Health Sciences Medicine Pharmacology

Tags

Alternative medicine Anesthesia Antidepressant Depression (economics) Dosing Economics Hippocampus Internal medicine Ketamine Macroeconomics Medicine Pathology Placebo Randomized controlled trial Treatment-resistant depression

Substances

Ketamine

Conditions & symptoms

Depression Lack of energy or motivation Sadness or low mood