Ketamine
Other names:
- K
- Special K
Basics: Ketamine is a synthetic drug not known to occur in nature. It is used widely as an anesthetic, especially for children and soldiers, and as an animal tranquilizer. It is also sometimes used to treat chronic pain. While it’s not entirely clear how ketamine works, the leading theory postulates that it acts on receptors for the neurotransmitter glutamate, which may play a role in regulating mood.
Clinically, ketamine is administered intravenously, by intramuscular injection, or as a lozenge placed under the tongue. Outside of medical settings, powdered ketamine is also snorted.
History: Ketamine was first synthesized in 1962. In 1970, the Food and Drug Administration approved the medicine, trade-named Ketalar, for use as an anesthetic.
Potential Benefits: At lower doses, ketamine can alter one’s perception and sense of time and space. At higher doses, the drug can cause a dissociative state, sometimes called a “k-hole,” during which people experience oblivion and are unable to perceive or interact with the outside world. These effects have some overlap with the general effect profile of classic psychedelics.
Potential Risks and Side Effects: Some participants in clinical trials reported side effects including headache, dizziness, nausea, blurred vision, drowsiness, and poor memory, but these resolved quickly after treatment sessions. Prolonged ketamine exposure has been associated with neurodegeneration in newborn rhesus monkeys. Some people become addicted to ketamine, which can be very difficult to overcome.
Therapy: Over the last twenty years, numerous studies have suggested that ketamine can be used to treat conditions including chronic depression, suicidal ideation, obsessive compulsive disorder, and post-traumatic stress disorder.
Legality: In the United States, ketamine is a Schedule III drug, meaning that it is legal when prescribed for medical use as an anesthetic. It can also be prescribed legally for off-label use, including for the treatment of depression. In 2019, the FDA approved Spravato, delivered as a nasal spray made from esketamine, half of the mirror image of ketamine, for use in treating treatment-resistant depression, or TRD. Because it is under patent, the price of Spravato can be hundreds of times the price of generic ketamine.
Licensed providers can legally offer ketamine-assisted therapy.
Notable Studies:
- The first placebo-controlled, double-blinded trial to use ketamine to treat depression.
- A randomized, placebo-controlled, double-blinded trial that used ketamine to treat bipolar depression.
- A study that demonstrated ketamine can also treat social anxiety disorder.
An article that describes how ketamine therapy is making scientists reconsider what we know about the biology of depression.
Selected Sources
History of anaesthesia: The ketamine story – past, present and future
European Journal of Anaesthesiology, 2018
Antidepressant effects of ketamine in depressed patients
Biological Psychiatry, 2000
A Randomized Add-on Trial of an N-methyl-d-aspartate Antagonist in Treatment-Resistant Bipolar Depression
JAMA Psychiatry, 2010
Ketamine for Social Anxiety Disorder: A Randomized, Placebo-Controlled Crossover Trial
Neuropsychopharmacology, 2018
FDA approves new nasal spray medication for treatment-resistant depression; available only at a certified doctor’s office or clinic
Food and Drug Administration Press Release, 2019