Ketamine

Our rating
1 smiley: This treatment is promising and may be useful. It has some evidence to support it, but more evidence is needed to be sure it works.

 

The rating system

  • 3 smiliesThese treatments are very useful. They are strongly supported as effective by scientific evidence.
  • 2 smiliesThese treatments are useful. They are supported by scientific evidence as effective, but the evidence is not as strong.
  • 1 smileyThese treatments are promising and may be useful. They have some evidence to support them, but more evidence is needed to be sure they work.
  • No smiley On the available evidence, these treatments do not seem to be effective.
  • Question markThese treatments have not been properly researched. It is not possible to say whether they are useful or not.
  • Exclamation MarkSafety or other concerns have been raised for the use of these treatments.

What is it?

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.

How does it work?

Ketamine is usually given as an intravenous (IV) fluid by a doctor in hospital. It can also be administered as a nasal spray or swallowed. 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.

Is it effective?

There is some scientific evidence on ketamine for the treatment of depression. Most studies have involved patients for whom other depression treatments have not been effective. 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.

One review of five studies found that ketamine can lead to positive effects for people with major depression for up to 6 weeks after treatment. However, it is not yet known whether ketamine can lead to long-term improvement in depression symptoms.

The current evidence is promising, however more large studies of better quality are needed.

Are there any disadvantages?

There are some side effects associated with ketamine, which can include feeling dizzy, confused, and out of touch with reality. Ketamine must be given under medical supervision and patients have to be monitored for some time after the medication is administered.

Where do you get it?

The use of ketamine as a treatment for depression is still experimental and mostly limited to hospital settings or as part of clinical trials.

Recommendation

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.

Key references

  • Bahji A, Vazquez GH, Zarate CA. Comparative efficacy of racemic ketamine and esketamine for depression: A systematic review and meta-analysis. Journal of Affective Disorders. 2021; 278:542-55.
  • Conley AA, Norwood AEQ, Hatvany TC, Griffith JD, Barber KE. Efficacy of ketamine for major depressive episodes at 2, 4, and 6-weeks post-treatment: A meta-analysis. Psychopharmacology. 2021; 238(7):1737-52.
  • Kryst J, Kawalec P, Mitoraj AM, Pilc A, Lasoń W, Brzostek T. Efficacy of single and repeated administration of ketamine in unipolar and bipolar depression: a meta-analysis of randomized clinical trials. Pharmacological Reports. 2020; 72(3):543-62.
  • Kraus C, Rabl U, Vanicek T, Carlberg L, Popovic A, Spies M, et al. Administration of ketamine for unipolar and bipolar depression. International Journal of Psychiatry in Clinical Practice. 2017; 21(1): 2-12.
  • Lee EE, Della Selva MP, Liu A, Himelhoch S. Ketamine as a novel treatment for major depressive disorder and bipolar depression: a systematic review and quantitative meta-analysis. General Hospital Psychiatry. 2015; 37(2): 178-84.
  • Nikolin S, Rodgers A, Schwaab A, Bahji A, Zarate C, Vazquez G, et al. Ketamine for the treatment of major depression: a systematic review and meta-analysis. eClinicalMedicine. 2023; 62:102127-.
  • McGirr A, Berlim MT, Bond DJ, Fleck MP, Yatham LN, Lam RW. A systematic review and meta-analysis of randomized, double-blind, placebo-controlled trials of ketamine in the rapid treatment of major depressive episodes. Psychol Med. 2015 Mar; 45(4): 693-704.
  • Smith-Apeldoorn SY, Veraart JKE, Spijker J, Kamphuis J, Schoevers RA. Maintenance ketamine treatment for depression: a systematic review of efficacy, safety, and tolerability. The Lancet Psychiatry. 2022; 9(11):907-21.

Last updated and reviewed: 22 December 2023

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