A pilot study randomly assigned 45 adults with major depressive disorder to receive either intramuscular ketamine (0.5 mg/kg), oral ketamine (1 mg/kg), or electroconvulsive therapy (ECT) over 3 weeks. Depression and suicidal ideation scores improved significantly in all groups, with no meaningful differences between the three treatments. Ketamine caused brief, transient dissociative symptoms, whereas ECT led to memory loss lasting up to a month in some patients. Patients who received ketamine preferred it over ECT. The authors suggest that oral and intramuscular ketamine may have antidepressant effects equal to ECT, with possibly greater antisuicidal effects, fewer cognitive side effects, and higher patient preference.
Intravenous ketamine and electroconvulsive therapy (ECT) produce similar improvements in depressive symptoms among adults with major depressive disorder. In a randomized trial with 32 patients, both treatments reduced depression severity on the Hamilton Depression Rating Scale, with no statistically significant difference between the groups. Cognitive function was slightly better in the ketamine group, though this difference was not statistically significant. Ketamine treatment did not cause memory deficits, unlike ECT which is often associated with cognitive side effects. The findings suggest ketamine may be a viable alternative to ECT for treating major depression.