Ketamine Research: How We Read the Evidence

Ketamine is FDA-approved as an anesthetic and has been used in operating rooms and emergency settings for decades, so its basic safety profile at anesthetic doses is well characterized. Esketamine (Spravato), a related nasal spray, is FDA-approved for specific depression indications and is dispensed under a restricted safety program. These are the settled facts.

IV ketamine used for depression, including treatment-resistant depression, is prescribed off-label — a common and legal medical practice that nonetheless means it is not FDA-approved for those uses. The evidence behind that off-label use is real: randomized, placebo-controlled trials have found that a single subanesthetic infusion can produce rapid, short-term reductions in depression symptoms for some adults whose depression had not responded to standard medications. Follow-up studies have examined repeated dosing and ways to maintain benefit.

Established does not mean universal. These trials measured averages across groups of carefully screened participants over weeks — they say nothing certain about any one individual over years.

For post-traumatic stress disorder, an early randomized controlled trial in 2014 reported symptom improvement after repeated ketamine infusions, and further trials are underway. For anxiety disorders, obsessive-compulsive disorder, and chronic pain conditions, the published literature is smaller and less consistent — mostly pilot studies, open-label work, and case series rather than large replicated trials.

Emerging evidence is a reason for careful hope and careful evaluation, not for bold claims. Where the research is early, ketamine therapy may be considered only after better-studied options have been tried, and only with honest counseling about how much remains uncertain.

Not all evidence carries the same weight. At the top sit randomized controlled trials, where participants are assigned by chance to the active treatment or a comparison, ideally with neither participants nor raters knowing which is which. Below those are open-label studies, where everyone knows the treatment being given — useful for safety and feasibility signals, but prone to placebo effects and expectation bias. At the base are case reports and case series, which describe individual patients and can generate hypotheses but cannot test them.

Ketamine is unusually hard to study blind, because its dissociative effects can reveal to participants which group they are in. We therefore give the most weight to findings that have been replicated across multiple controlled trials by different research groups, and we treat single small studies — positive or negative — as provisional.

Genuine open questions remain, and we think you deserve to hear them plainly. Researchers do not yet know how durable the benefit of ketamine is for most people, which maintenance strategies — if any — work best over the long term, or how to predict in advance who is most likely to respond. Long-term outcomes of repeated ketamine treatment for mood disorders are still being studied.

The FDA has also warned about potential risks tied to compounded ketamine products used without adequate safeguards, which is one reason we insist on a clinical setting, screening, and monitoring rather than unsupervised use.

Our evaluation process, consent conversations, and treatment planning are built around this evidence picture. When we discuss ketamine therapy with you, we distinguish what is established from what is emerging, we explain off-label status in plain terms, and we cite primary sources — several of which are listed below — so you can read them yourself.

If new high-quality evidence changes the picture, our policies change with it. That is what reading the evidence, rather than marketing around it, requires.