an NMDA receptor antagonist that is usually used in anesthesia in humans and animals. Often delivered as an infusion or intramuscularly, or as a cream or gel (often in combination with other analgesics), Ketamine is effective, at least in the short term, in treating several chronic pain states including complex regional pain syndrome and fibromyalgia as well as difficult to treat cases of depression.
Ketamine might work in Fibromyaglia or Chronic Fatigue Syndrome (ME/CFS) Because…
It appears to reduce the central nervous system sensitization associated with increased pain in both disorders. An NMDA receptor inhibitor Ketamine also appears to reduce the activity of glutamate, the main excitatory neurotransmitter in the brain. Glutamate excitotoxicity has been linked to fibromyalgia, depression, multiple sclerosis and possibly chronic fatigue syndrome (ME/CFS). Ketamine’s ability to enhance circulatory functioning is intriguing given the low blood volume and other possible circulatory issues in ME/CFS.
Chronic Fatigue Syndrome (ME/CFS) and Fibromyaglia Studies
No studies have examined Ketamine’s effectiveness in ME/CFS but several studies have examined it’s effectiveness in Fibromyalgia. Given the need for infusions and Ketamine’s short-lived effects Ketamine may, however, be more important for what it tells researchers about Fibromyalgia than as an actual treatment aid.
Dutch researchers recently found 30-minute Ketamine infusions reduced pain levels in fibromyalgia by 50% but the effect was too short-lived, lasting less than 2 hours, to justify more treatment. In a 2007 French study subcutaneous Ketamine reduced pain levels and increased blood flows in parts of the brain associated with pain regulation in Fibromyalgia patients. An associated study suggested that a negative response to Ketamine in Fibromyalgia was associated with an inability to increase blood flows to the medial frontal gyrus. These areas of the brain appear to be important in producing pain in FM patients. (Ketamine increases heart rate and blood pressure).
A successful 2000 Danish study able to reduce both local and referred pain suggested Ketamine was reducing central nervous system ‘hyperexcitability’. In a 2006 review article Wood suggested the positive response to Ketamine in fibromyalgia was not due to NMDA receptor inhibition but to increasing dopamine levels in limbic system neurons.
Ramachandran proposed Ketamine’s anesthetic properties might be helpful in ‘dissociative disorders’ such as Fibromyalgia where patients attempt to dissociate themselves from their pain. Ketamine is known to create states of ‘dissociative anesthesia’ and, not surprisingly, has been used a recreational drug.
Chronic Fatigue Syndrome (ME/CFS) and Fibromyaglia Doctors Report
Dr. Podell reports that Ketamine reduces pain in about 50% of his fibromyalgia patients. Ketamine was a key component of Dr. Jay Goldstein’s (now retired) “resurrection cocktail‘. Goldstein administered Ketamine intravenously or through a gel. The resurrection cocktail often included ascorbate, lidocaine and thyrotropin-releasing hormone. One report stated that 50% of Goldstein’s patients felt dramatically better after the cocktail.
ME/CFS and Fibromyalgia Patients Report
One fibromyalgia patient with severe back issues reported that ketamine is the only drug that helps her and that one infusion reduces her pain for a 8 to a 2-3 for several weeks.
Ketamine’s effects on perhaps the most tenacious pain disorder, complex regional pain syndrome, have been startling. Ketamine produced complete and sometimes long term remission in all CRPS patients in one study. Other placebo-controlled, randomized studies using long infusion times have produced significant reductions in pain lasting up to three months. One author has argued that fibromyalgia and CRPS share numerous similarities – including a positive response to ketamine.
One review stated that “on the basis of a few short term trials with limited clinical applications, ketamine may be effective in the treatment of chronic peripheral and central neuropathic pain, phantom and ischemic limb pain, fibromyalgia, chronic regional pain syndrome (CRPS), visceral pain and migraine”.
Ketamine works in a large subset of fibromyalgia patients but its expense and finding a doctor to administer it have blunted its use in that disorder. Some people travel out of the country to get less expensive ketamine infusions.
Ketamine’s remarkable ability to relieve severe pain and/or depression in some patient, however, has sparking substantial research. Three molecular targets have been identified for depression and drug companies are developing easier to use ketamine derivatives – some of which are in clinical trials now.
Ketamine’s real promise for most FM and chronic pain patients lies in the future.