Ketamine infusions for patients with treatment-resistant depression
What is it about?
Small doses of ketamine administered intravenously can rapidly relieve depressive symptoms, but these effects are not long lasting. We showed that a single infusion of ketamine has superior antidepressant effects compared to an active placebo medication using a crossover design (each participant received a trial of each medication). With repeated ketamine infusions administered three times weekly, we demonstrated a cumulative decrease in depressive symptoms and a doubling in the number of patients who responded to treatment compared to the single infusion. Further, we tested a novel maintenance strategy for intravenous ketamine and showed that antidepressant effects can be maintained when the frequency of infusions is reduced to once weekly.
Why is it important?
This clinical trial confirms that ketamine infusions can provide safe and effective reductions in depressive symptoms in patients resistant to other forms of treatment. The novel information on the effects of repeated and maintenance infusions aimed at maximizing and prolonging the antidepressant effects of ketamine further inform the use of ketamine in clinical practice. Effective ketamine administration strategies will permit sustained therapeutic benefits for patients.