Ketamine Outperforms Shock Therapy for Depression: Study

2 min read

May 30, 2023 – The desensitizing drug ketamine helped more people overcome treatment-resistant depression symptoms than electroconvulsive (shock) therapy, according to a new study. 

More than half of people with depression who didn't respond to antidepressants saw improvement in their symptoms after getting twice weekly ketamine infusions, while 41% of people treated with electroconvulsive therapy (ECT) saw improvement.

Ketamine causes a psychedelic effect called disassociation and has been shown in previous studies to have a rapid impact on depression symptoms. ECT therapy passes small electric currents through the brain and triggers a short seizure, and it's believed to change brain chemistry linked to mental health.

The findings are important because about 30% of the 21 million people in the U.S. with major depression have the treatment-resistant kind, meaning that at least two antidepressant drugs haven’t worked for them. 

“ECT has been the gold standard for treating severe depression for over 80 years,” said researcher Amit Anand, MD, a psychiatrist at Mass General Brigham and a professor at Harvard Medical School, in a statement. “But it is also a controversial treatment because it can cause memory loss, requires anesthesia, and is associated with social stigma. This is the largest study comparing ketamine and ECT treatments for depression that has ever been done, and the only one that also measured impacts to memory.”

The 365 people in the study had all been invited to participate in the research after being referred for treatment at ECT clinics for treatment-resistant major depression. They were randomly assigned to either participate in ketamine or ECT treatment for 3 weeks. The people who were treated with ECT had treatments three times per week, and the people who were treated with ketamine had treatments twice per week. 

The findings were published last week in the New England Journal of Medicine.

The ketamine used in the study was given through an IV. A nasal spray form of the drug was approved by the FDA in 2019. 

Anand and fellow researchers are now studying the impacts of ECT and ketamine for people with acute suicidal depression.

“People with treatment-resistant depression suffer a great deal, so it is exciting that studies like this are adding new options for them,” Anand said. “With this real-world trial, the results are immediately transferable to the clinical setting.”