“To help best ensure patient safety and to minimize risks, it is strongly advised that site-specific standard operating procedures be developed and followed for the delivery of ketamine treatments for major depressive episodes,” the authors recommend.

Summing up, Dr. Sanacora and colleagues say, “The rapid onset of robust, transient antidepressant effects associated with ketamine infusions has generated much excitement and hope for patients with refractory mood disorders and the clinicians who treat them. However, it is necessary to recognize the major gaps that remain in our knowledge about the longer-term efficacy and safety of ketamine infusions. Future research is needed to address these unanswered questions and concerns.”

The co-authors of an invited commentary say there is “little doubt that ketamine is having a major effect on psychiatry” and this “much-needed” consensus will help guide its clinical use.

“The consensus statement by Sanacora and colleagues, however, provides a sobering cautionary guide, especially as we move toward attempting to sustain the gains achieved by acute doses of ketamine. This consensus statement will not be the final word on this topic, and similar considerations will be needed for other novel treatments,” write Dr. Charles Zorumski and Dr. Charles Conway of Washington University School of Medicine in St. Louis, Missouri.

The consensus authors also “highlight the importance of enrolling patients in systematic studies to advance the field, rather than simply using ketamine in open and uncontrolled ways. We strongly endorse the authors’ call for a registry of patients treated with ketamine to allow coordinated data collection and to provide a monitor about ketamine use,” Drs. Zorumski and Conway say.

Several consensus authors disclosed financial relationships with various pharmaceutical companies.