Could intravenous (IV) ketamine ease depression symptoms quickly? A 2026 systematic review and meta-analysis in JAMA Psychiatry examined that question, including whether ketamine infusions were associated with changes in suicidal symptoms.
The researchers combined results from 26 randomized clinical trials involving 1,166 people experiencing a major depressive episode. Across the studies, IV ketamine was compared with control treatments such as saline or midazolam. The authors found that depression symptom scores improved more quickly in the ketamine groups at several measured time points.
What did the review find?
After a single ketamine infusion, the pooled studies found lower depression symptom scores in the ketamine groups compared with control groups at:
– 4 hours
– 24 hours
– 3 days
– 1 week
For suicidal symptoms, the review found lower scores at 24 hours after a single infusion. It also found lower scores at a one-month assessment in the studies reporting that time point. In studies using repeated infusions, suicidal and depression symptom scores were lower at the end of treatment compared with control groups.
These are results averaged across studies. They don’t tell us exactly how a particular person will respond, and they don’t mean every patient experiences improvement.
What do the results mean for someone considering ketamine?
The review adds to research suggesting that IV ketamine may have a rapid effect on symptoms for some people during a major depressive episode. That timing differs from many standard antidepressants, which may take weeks to show their full effect.
However, a rapid change in symptom scores is only one part of depression care. A treatment decision needs to take into account a person’s diagnosis, health history, current medications, symptoms, and other treatment options.
What are the study’s limitations?
A meta-analysis combines findings from multiple studies, which can offer a broader view than one trial. But it also depends on the quality and consistency of the studies being combined.
The included trials used different control treatments, infusion schedules, and ways of measuring symptoms. Follow-up was limited for many outcomes, so the results say more about short-term symptom changes than about how long benefits last, whether symptoms return, or what ongoing treatment should look like.
The results describe what happened on average in clinical trials. They cannot predict the outcome for an individual patient.
Is IV ketamine FDA-approved for depression?
Ketamine itself is FDA-approved as an anesthetic, but IV ketamine is not FDA-approved as a depression treatment. Its use for depression is considered off-label. The meta-analysis studied IV ketamine; it did not study Spravato® (esketamine) nasal spray, which is a different medication with separate FDA-approved uses.