Ketamine is an anesthetic medication that is usually used in medical settings to sedate patients. It has been researched as fast-acting antidepressant, usually for patients who don’t respond well to other forms of treatment. Ketamine is also used as an illegal recreational drug.
Ketamine is usually given as an intravenous (IV) fluid by a doctor in hospital. The dose used to treat depression is lower than what would be given to produce anesthetic effects. Ketamine is thought to work by blocking certain receptors in the brain that are involved in cell growth, which may be over-active in people with depression.
There is some scientific evidence on ketamine for the treatment of depression. While more studies of better quality are needed, the current evidence is promising. Patients who have been given a low-dose of ketamine in hospital often report fast acting (within hours) improvement in their depression symptoms. This in in contrast to typical antidepressant medication, which usually take many weeks to produce an effect. There is no research looking at the long term effectiveness of ketamine.
There are some side effects associated with ketamine, which can include feeling dizzy, confused, and out of touch with reality. Currently, ketamine for depression is administered via IV line in a hospital setting and patients have to be monitored for some time afterwards. Ketamine must be given under medical supervision.
The use of ketamine as a treatment for depression is still experimental and mostly limited to hospital settings or as part of clinical trials.
More research is needed, but ketamine may be a useful fast-acting antidepressant in the future.
Ketamine is currently classed as a controlled drug in Australia, and unauthorised possession or use may result in criminal penalties.
Last updated and reviewed: 1 November 2019