Ketamine is a sedating agent used to induce anesthesia. It is also a drug of abuse with street names such as “Special K” or “Ket”.
Ketamine has many advantages, which makes it a very popular choice in anesthesia. It works fast, blocks pain, opens the lungs, it is easy on the heart, and has anti-inflammatory properties. It may also have anti-cancer properties. Ketamine is being extensively tested for the treatment of depression that does not respond to medications.
Because ketamine works on a receptor involved in transmitting pain messages in the brain (NMDA receptor), it has been studied in various painful conditions. The amounts being tested for pain are much smaller than those used to induce anesthesia or even those used recreationally.
Even though it is a drug of abuse, it appears to be less addictive than heroine and prescription narcotics.
There are only few small studies and reports about the use of ketamine for migraine headaches. One such report published in the leading neurological journal Neurology describes 18 patients with prolonged migraine auras who were treated with intranasal ketamine spray. The duration of their auras was not shortened by ketamine, but the severity was reduced.
Another study showed that severe disabling aura was relieved in 5 out of 11 patients with hemiplegic migraine.
Several anecdotal reports have touted the benefits of ketamine in chronic migraines, cluster headaches, and chronic paroxysmal hemicrania (a rare type of headache that often responds to indomethacin and at times to Botox). While such anecdotal reports are useful, we need to have controlled trials to make sure that placebo effect is not playing a major role. There is nothing wrong with utilizing the placebo effect, but only if the treatment is completely benign. Unfortunately, ketamine like any other drug can have potentially serious side effects. This is why before treating pain with ketamine intravenously patients must be screened for possible heart disease or psychiatric disorders such as schizophrenia. While intranasal ketamine can be given in an office setting, intravenous administration must be done under close monitoring. Another issue is the cost since insurance companies do not cover this treatment because it is considered experimental.
