PeaPure – Palmitoylethanolamide for Nerve Pain or Migraine


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PeaPure is a glial modulator. It is available in Italy and the Netherlands as a food supplement and has been studied in multicenter clinical trials in Europe for several years. It is well tolerated with no side effects and is very helpful for neuropathic pain, headache, and osteoarthritis. It is anti-inflammatory and neuroprotective.

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Because it inhibits astrocyte activation and the over-expression of pro-inflammatory molecules and signals, it is being investigated in Alzheimer’s Disease.

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The mechanism of action of PEA was discovered in 1993 by Nobel laureate Rita Levi-Montalcini in her work on nerve growth factors. She found it is involved in metabolism of mast cells and published a series of papers on its self-healing effect of the body in response to inflammation and pain. Two recent publications from Jan M Keppel Hesselink, MD, PhD, and his colleagues at the Institute for Neuropathic Pain, Amsterdam, The Netherlands, describe case reports, one of which is the case of a woman with CRPS.

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The purpose of this post is to clarify dosing of PeaPure and how to take it for a sudden flare of pain. My apologies for failing to recall the source of these instructions which I believe was from the manufacturer and from here and here. The latter includes an excellent review of its mechanism.

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Description of PeaPure® 400 mg capsules
PeaPure® is a food supplement based on a natural and fatty-acid like compound.
The substance palmitoylethanolamide (PEA) is a physiologically active molecule that the body produces naturally.
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What the user should know prior to ingestion:
•    There are no known significant side effects.
•    PeaPure® can be taken simultaneously with other medicine. In case of doubt, it is recommended to first consult your doctor or a pharmacist.
•    Use during pregnancy is NOT recommended.
•    PeaPure® does not contain sugar, yeast, allergens, sorbitol, magnesium stearate, povidone or other ingredients.

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Dosage and administration – please refer to the manufacturer.

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UPDATE SEPTEMBER 2014

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It is with a heavy heart that I report this news:

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Palmitoylethanolamide is

now available only from the Netherlands,

sold as PeaPure, a food supplement.

  It is no longer able to be imported by a pharmacy, but we are hoping

that may change if we can interest a supplement manufacturer to make it available for the US.

Patent rights, attorneys are far beyond the resources of my local pharmacy.

 

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I have published this year, 2014, on the treatment of

vulvodynia and proctodynia with PeaPure and a topical cream.

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There are no studies to show us how often it may relieve nerve pain, but it is astonishing when it works. No toxicity, no side effects. Your brain makes it, plants make it. There is a growing literature on it and I have posted on some of its mechanisms. And in particular, its Anti-inflammatory, Analgesic, Neuroprotective Mechanisms.

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The material on this site is for informational purposes only, and is not a substitute for

medical advice, diagnosis or treatment provided by a qualified health care provider.

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Please understand that it is not legal for me to give medical advice without a consultation.

If you wish an appointment, please telephone my office or contact your local psychiatrist.

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For My Home Page, click here:  Welcome to my Weblog on Pain Management!

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Ketamine Intranasal for Rapid Relief of Pain and Depression


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Poorly managed pain can evolve into chronic disease of the nervous system

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Ketamine is an important analgesic, more important than opioids. It can dramatically reduce pain, and rapidly relieve depression and PTSD.  Please read my earlier posts here and here. And the NPR report here just after I posted this (skip to their last section). Yes, it is FDA approved and legal. One woman said:

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 ‘It was almost immediate, the sense of calmness and relaxation.

‘No more fogginess. No more heaviness. I feel like I’m a clean slate right now. I want to go home and see friends or, you know, go to the grocery store and cook the family dinner.’

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NPR again reports ketamine’s rapid relief of depression. A 28 year old man whose refractory depression began at age 15, after ketamine, says:

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‘I Wanted To Live Life’

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Stephens himself has vivid memories of the day he got ketamine. It was a Monday morning and he woke up feeling really bad, he says. His mood was still dark when doctors put in an IV and delivered the drug.”Monday afternoon I felt like a completely different person,” he says. “I woke up Tuesday morning and I said, ‘Wow, there’s stuff I want to do today.’ And I woke up Wednesday morning and Thursday morning and I actually wanted to do things. I wanted to live life.”.
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Since then, they treated him with Riluzole that is FDA approved for ALS and has one of the dirtiest side effect profiles I have ever seen in medicine with serious organ toxicity. Ketamine rarely causes mild transient side effects, usually none. It appears the concern is how ketamine is used on the street with potential for abuse. I do not see ketamine abuse in my patients, some of whom are on opioids for pain or Valium family medicines from their psychiatrist. All of those have a greater potential for abuse, also not occurring in my patients. Pain and/or depression can lead to suicide.
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About 18 months ago, researchers at Yale found a possible explanation for ketamine’s effectiveness. It seems to affect the glutamate system in a way that causes brain cells to form new connections.
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Researchers have long suspected that stress and depression weaken some connections among brain cells. Ketamine appears to reverse the process.

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It would be of interest to see a case report of the bladder problems they mention. Is this in a single drug addict who used many unknown medications on the street? Several physicians have infused IV ketamine for persons with pain for many years, in far higher doses than I prescribe, with no report of any but transient minor symptoms.

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David Barsook’s 2009 review, reference below, describes changes that cause memory loss and brain atrophy with chronic pain, in particular, Complex Regional Pain Syndrome (CRPS), and they also occur with chronic depression:

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With the onset of chronic pain (including CRPS) a number of changes in brain function occur in the human brain including but not limited to: (1) central sensitization ; (2) functional plasticity in chronic pain and in CRPS; (3) gray matter volume loss in CRPS ; (4) chemical alterations; and (5) altered modulatory controls. Such changes are thought to be in part a result of excitatory amino acid release in chronic pain. Excitatory amino acids are present throughout the brain and are normally involved in neural transmission but may contribute to altered function with excessive release producing increased influx of calcium and potentially neural death.

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Brain atrophy and memory loss has also been shown in chronic low back pain as well as in chronic depression.

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Barriers to management of chronic pain are many:

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Although opioids are effective for acute pain, effective treatment of chronic pain is often daunting, particularly neuropathic pain.

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Opioids have been shown to create pain causing imbalance in the glial cytokines that favor pain rather than relief of pain. Opioids carry the risk of opioid-induced hyperalgesia which is a severe pain sensitivity. They affect the brain and endocrine system. Opioids may fail to offer significant relief, fail to improve function, and risk misuse, abuse, diversion and death. Their costs are astronomic, insurance coverage is increasingly limited, the potential for complications may be life threatening in a hectic medical setting, side effects can be lethal, lack of physician training in use of opioids and alternatives to pain control lead to increasing deaths, addiction and diversion. It has become a national emergency and a trillion dollar war on drugs.

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Complications can be greatly reduced through use of a scrupulous history and physical examination, but reimbursement is directly proportional to the shortest time spent with a patient. Will that help assessment and care?

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Individuals may have dramatically different responses to opioid therapy; some may not tolerate any, and relief must be balanced with side effects that increase as the dose increases. Patient status may change and require IV, rectal or tube delivery instead of oral formulas; drug-drug interactions may require rapid changes, and disease of kidney, liver or brain may require modifications or stopping altogether. They may increase risk of falls and cause central sleep apnea with drop in oxygen because the brain fails to give a signal to breathe.

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Chronic pain can lead to loss of sleep, hopelessness, depression, anger and other mood disorders such as panic, anxiety, hypochondriasis and post traumatic stress disorder [PTSD]. Treatment of mood disorders are shown to profoundly reduce pain perception and/or ability to cope with pain.

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Ketamine is anti-inflammatory and can reduce the need for opioid use, thus reducing the pain and side effects caused by opioids.

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Nasal ketamine is more effective than oral ketamine for pain relief; oral dosing has no effect on depression.

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Nasal delivery of ketamine is now possible due to advances in metered nasal sprayers that deliver a precise dose. No needle is required, no IV access, no travel to a specialist needed.

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You can carry pain relief with you and use it as directed when it is needed.

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Ketamine is an NMDA antagonist: it antagonizes the NMDA receptor which plays a profound role in pain systems and centralization of pain.

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Ketamine is neuroprotective and it can help other disease states as noted by Barsook, 2009:

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Besides improvement in pain, “there may be lessons from other diseases that affect the brain; it is noteworthy that acute ketamine doses seem to reverse depression and ketamine decreased prevalence of post-traumatic stress disorder (PTSD) in soldiers receiving ketamine during their surgery for treatment of their burns. In addition ketamine attenuates post-operative cognitive dysfunction following cardiac surgery that has been known to produce significant changes in cognition. [emphasis mine] The data suggest that the drug can alter or prevent other conditions based on its NMDAR activity where other drugs NMDA receptor antagonists are perhaps not as effective in these or pain conditions. Lastly, NMDA antagonists have been used in degenerative disease (and pain may be considered a degenerative disease as defined by loss of gray matter volume, see above) with mixed effects perhaps relating to how they act on specific NMDA subtypes. Taken together, ketamine may act not only on sensory systems affecting pain intensity, but also on a constellation of brain regions that are involved in the pain phentype. [sic, phenotype]”

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Side Effects

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Ketamine is more frequently used in babies and children than in adults because high doses of ketamine can induce hallucinations in the adult. Importantly, it is used in high dose in adults for treatment of Complex Regional Pain Syndrome.

Low doses, cause little or no side effects in adults. If present, they are transient and often resolve in 20 minutes. Patient who respond to ketamine report good acceptance as they find the relief of pain and/or depression far outweighs any short term minimal discomfort.

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Pain care reform is urgently needed.

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Research funding for pain is less than half of one percent of the NIH budget. More research is needed, but research on low dose ketamine for treatment of pain and depression has gone on for twenty years.

The public health crisis of untreated pain, which often results in disability, parallels the country’s struggle to halt the cost of health care. The longer a person remains with untreated pain, the less likely they are to return to work or to be employable.

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Conclusion

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Pain control requires urgent attention. It is past time to put into practice the use of this valuable medication so people can get on with life instead of being mired in chronic pain that for many risks suicide and ensures continuing decades of disability. Academic studies are usually limited by defining a predetermined dose rather than clinically titrating to effect. Thus no surprise, they find no effect as every patient will have no response until they reach their dose. And that dose, in my experience, falls into a bell shaped curve. One size does not fit all. Some respond at very low dose, others require much more, and the majority fall between.

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In my experience prescribing ketamine for ten years, only a rare person has problems. Almost all find it has returned function or significantly relieved pain. Some have been able to entirely eliminate opioids that did nothing for their pain for decades, though they dutifully returned to the MD every month to chronicle that pain. Pain continued to be rated ten on a scale of ten; patient always compliant despite side effects of constipation and often depression. My patients find the benefits of nasal ketamine far outweigh the relief of oral ketamine and at much lower doses with fewer side effects.

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Further, while the pain relief may be short lived, some find it gets better with repeat dosing, and relief of depression may last one to two weeks with a single dose.

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References

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http://www.wjgnet.com/1007-9327/10/1028.asp  Ketamine suppresses intestinal NF-kappa B activation and proinflammatory cytokine in endotoxic rats.

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CONCLUSION: Ketamine can suppress endotoxin-induced production of proinflammatory cytokines such as TNF-a and IL-6 production in the intestine. This suppressive effect may act through inhibiting NF-kappa B.

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http://informahealthcare.com/doi/abs/10.1080/J354v16n03_03  Ketamine as an Analgesic Parenteral, Oral, Rectal, Subcutaneous, Transdermal and Intranasal Administration

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Ketamine is a parenteral anesthetic agent that provides analgesic activity at sub-anesthetic doses. It is an N-methyl-D-aspartate (NMDA) receptor antagonist with opioid receptor activity. Controlled studies and case reports on ketamine demonstrate efficacy in neuropathic and nociceptive pain. Because ketamine is a phencyclidine analogue, it has some of the psychological adverse effects found with that hallucinogen, especially in adults. Therefore, ketamine is not routinely used as an anesthetic in adult patients. It is a frequently used veterinary anesthetic, and is used more frequently in children than in adults. The psychotomimetic effects have prompted the DEA to classify ketamine as a Schedule III Controlled Substance. A review of the literature documents the analgesic use of ketamine by anesthesiologists and pain specialists in patients who have been refractory to standard analgesic medication regimens. Most reports demonstrate no or mild psychotomimetic effects when ketamine is dosed at sub-anesthetic doses. Patients who respond to ketamine tend to demonstrate dramatic pain relief that obviates the desire to stop treatment due to psychotomimetic effects (including hallucinations and extracorporeal experiences). Ketamine is approved by the FDA for intravenous and intramuscular administration. Use of this drug by the oral, intranasal, transdermal, rectal, and subcutaneous routes has been reported with analgesic efficacy in treating nociceptive and neuropathic pain.
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http://www.ncbi.nlm.nih.gov/pubmed/15109503  Safety and efficacy of intranasal ketamine for the treatment of breakthrough pain in patients with chronic pain: a randomized, double-blind, placebo-controlled, crossover study  Daniel Carr, et al, 2004
Crossover, 20 patients. Ketamine reduced breakthrough pain within 10min of dosing, lasting up to 60min
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http://www.ncbi.nlm.nih.gov/pubmed/15288418  Safety and efficacy of intranasal ketamine in a mixed population with chronic pain
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The intranasal route for ketamine administration has been applied only for pain of dressing changes in a single case study (Kulbe, 1998). In this patient, oxycodone and acetaminophen were ineffective to control pain during burn dressing changes in a 96-year-old woman cared for at home. She tolerated the burn dressing changes after three intranasal sprays of 0.1 ml each, in rapid succession, each containing 5 mg ketamine (15 mg total) (Kulbe, 1998).
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http://www.acutepainjournal.com/article/S1366-0071%2807%2900167-2/abstract  Safety and efficacy of intranasal ketamine for acute postoperative pain
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Ketamine delivered intranasally was well tolerated. Statistically significant analgesia, superior to placebo, was observed with the highest dose tested, 50 mg, over a 3 h period. Rapid onset of analgesia was reported (<10 min), and meaningful pain relief was achieved within 15 min of the 50 mg dose. The majority of adverse events were mild/weak and transient. No untoward effects were observed on vital signs, pulse oximetry, and nasal examination. At the doses tested, no significant dissociative effects were evident using the Side Effects Rating Scale for Dissociative Anaesthetics.
The safety profile following treatment with ketamine was comparable to that seen with placebo.
Although patients did report side effects of fatigue, dizziness and feelings of unreality more often following treatment with ketamine than following treatment with placebo, no patient reported hallucinations and the side effects were generally reported to be of mild or moderate severity, and transient. No serious adverse events were reported and the incidences of associated adverse events were comparable for ketamine and placebo. Although study medication was administered intranasally, nasal signs and symptoms were few and inconsequential. A distinctive taste, however, was reported more often following treatment with ketamine than following treatment with placebo.In conclusion this randomized, placebo-controlled, double-blind study, in 20 patients, has demonstrated that intranasal ketamine is safe and effective for BTP [breakthrough pain]. Our findings augment an early but promising literature documenting the effectiveness of nasal administration of a variety of opioids for pain management in adults (Dale et al., 2002) .
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~http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2875542/

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2875542/  Ketamine and chronic pain – Going the distance, David Barsook, 2009

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This important paper covers essential points not mentioned by many, thus quoted at length below:

“Ketamine, brain function and therapeutic effect – neuroprotective or neurotoxic

With the onset of chronic pain (including CRPS) a number of changes in brain function occur in the human brain including but not limited to: (1) central sensitization ; (2) functional plasticity in chronic pain and in CRPS; (3) gray matter volume loss in CRPS ; (4) chemical alterations ; and (5) altered modulatory controls. Such changes are thought to be in part a result of excitatory amino acid release in chronic pain. Excitatory amino acids are present throughout the brain and are normally involved in neural transmission but may contribute to altered function with excessive release producing increased influx of calcium and potentially neural death. Here lies the conundrum the use of an agent that potentially deleteriously affect neurons that may already be compromised but may also have neuroprotective properties by mechanisms that include reducing phosphorylation of glutamate receptors resulting in decreased glutamatergic synaptic transmission and reduced potential excitotoxicity . Alternatively, ketamine may affect glia regulation of glutamate and inhibit glutamate release within glia. However, by whatever mechanism ketamine acts on CRPS pain, there does seem to be a dose/duration effect in that longer doses at levels tolerated by patients seem to prove more effective in terms of the duration of effects.

So what could be happening in the brain and what is required to alter brain systems and reverse the symptomatic state? Ketamine may diminish glutamate transmission and “resets” brain circuits, but it seems that a minimal dose and/or duration of treatment is required. Alternatively, ketamine may produce neurotoxicity and damage or produce a chemical lesion of affected neurons. These two issues are important to be understood in future trials. Reports from patients who have had anesthetic doses have included prolonged pain relief for many months. While the authors did not address issues such as the effect of dosing duration or repetitive dosing at say 6weeks, they did show a level of efficacy based on NNT that equals or betters most drug trials for this condition.”

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“Conclusions

As a community we have a major opportunity to define the efficacy and use of a drug that may offer more to CRPS (and perhaps other) patients than is currently available. This is clearly an opportunity that needs urgent attention and a number of questions remain to be answered. For example, is ketamine more effective in early stage disease? How does ketamine provide long-term effects? Further controlled trials evaluating dose, duration, anesthetic vs. non-anesthetic dosing are needed. Few of us really understand what it is like to suffer from a chronic pain condition such as CRPS. Ketamine therapy may be a way forward that can be brought into our clinical practice through further controlled studies that will allow for appropriate standards for use in patients.”

 

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The material on this site is for informational purposes only, and is not a substitute for medical advice,
diagnosis or treatment provided by a qualified health care provider.
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~

Please understand that it is not legal for me to give medical advice without a consultation.

If you wish an appointment, please telephone my office or contact your local psychiatrist.

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For My Home Page, click here:  Welcome to my Weblog on Pain Management!
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Ketamine


Ketamine for persons with severe pain

cancerIn special circumstances, I may suggest a trial of low dose oral ketamine. It is formulated by a compounding pharmacist as an oral suspension. It is safe to use without significant adverse effects, though you may experience transient symptoms lasting 20 to 40 minutes after the first few doses. For most people, it may relieve pain when all other methods have failed, possibly including total pain relief with no side effects in patients who have then been able to discontinue all opioids.

Keep all your medicine, opioids and ketamine, in a lock box to prevent abuse by others. This is a Schedule III drug like Vicodin.

Achieving control of chronic pain requires a partnership

based upon trust and effort

Requirements: I will work closely with you on ketamine and ask you to keep a log of pain before each dose and 30 minutes after. In addition, for the first week I ask that you log blood pressure and heart rate before each dose and 30 minutes after. This requires that you see me in the office one week later. If you have any questions or problems, I ask that you call me the same day, whether it be weekend or holiday. If you are unable to keep these logs before and after the dose, and the appointment one week later, the trial will be discontinued. You have no authority to continue without my consent.

Blood Pressure: Usually no change occurs in blood pressure. Some have reported that ketamine lowers their blood pressure and they are lightheaded when they stand up. If your blood pressure drops or if you are lightheaded, be very cautious as that may lead to fainting and brief loss of consciousness. Anytime a person faints, that could result in potentially serious injury such as hip fracture, other fractures, bleeding or brain injury if you strike your head. Your blood pressure should be above 100 when standing.  Ketamine has been reported to increase blood pressure and pulse, but I have not found that to occur with these doses.

Side Effects: Ketamine has a very narrow therapeutic window for pain control. This means that once you find the dose that relieves pain, a very slight increase in dose may produce intolerable side effects. Unfortunately some patients reach a dose that produces side effects before they experience any pain relief.

Most patients have no side effects with the low doses used by this protocol, though some may have mild symptoms lasting up to 40 minutes. If you do, then try decreasing the dose a small amount.

It is possible but rare that you may experience severe, frightening hallucinations or may feel you are outside the body observing it do things, called a dissociative reaction.

These side effects are dose related and have been short lasting, usually no longer than 40 minutes.  The antidote is Ativan.

Steps to follow: Read all steps carefully before you begin

  • Take ketamine 30 minutes prior to your other pain medication
  • For the first dose, remain seated or lie down for 20 minutes after you take the dose to avoid risk of falling. Do not take the dose and walk around.
  • A few persons have had severe imbalance lasting 10 or 20 minutes. This has resolved after the first few doses in those persons. It may not happen to you, so test with caution. If it has not occurred at the first dose, it is unlikely to occur at all.
  • Follow the dosing guidelines in the log I give you and which I repeat in this next step:
    Begin with 0.25 mL and increase by increments of 0.25 mL every 6 hours or longer than 6 hours, until you have some pain relief. Do not increase that dose or dosing interval.

Example: begin 0.25 mL, then 0.5, next 0.75, 1.0, 1.25, 1.5, 1.75, 2.0

If you have had no effect on pain by 2.0 mL, schedule an appointment for further instructions.
If your pain decreases only 1 or 2 points, that is your dose.  It will NOT get better by increasing the dose.  Stop increasing.

  • If you have intolerable side effects, you may use 1 or 2 Ativan tablets immediately as an antidote, and every 30 minutes, up to 5 of them.
  • CAUTION: Be alert to the opioid-sparing effects of ketamine!

This means that if ketamine relieves your pain, you do not need to take the opioid as that would be an opioid overdose and may cause serious side effects.

Reduce or temporarily stop your opioid medication if pain is gone after using ketamine.

This is why you take ketamine 30 minutes before the opioid. Some people have been able to completely stop all opioid medication due to pain relief from ketamine alone.

  • CAUTION: Do not drive for 6 hours after a dose.

This is for the protection of you and others. You may not be aware of very subtle side effects.

  • You may take a dose every 6 hours, or longer than 6 hours. Less is more.

If ketamine loses its effect, stop use for 2 or 3 days, then resume. It can be a fickle drug.  That is why increasing the dose causes loss of effect.

Some take ketamine only before sleep. If you do that, use it 30 minutes before sleep in order to log its effect and take blood pressure/pulse before and after. Continue this initially until further changes are approved.

Ketamine was approved for use as an anesthetic by the FDA in 1970

It’s use for pain is “off label” as it was approved only in high doses for anesthesia. It has been used safely in babies. Unlike opioids, it does not depress breathing or bowel function, and usually does not depress cardiovascular function. Since the late 1980’s, numerous scientific articles have been published on its use as a third line choice for some pain conditions; there are few double blind control studies, one is listed below. If you search ketamine on various internet search engines you find it is abused by addicts just as other drugs are. You find medical articles when you search the literature using Google Scholar or PubMed in the National Library of Medicine. If you find a medical article with adverse effects, let me know. I have spoken to leading brain and psychiatric researchers who have verified there are no lasting side effects from its use.

Many publications on ketamine use multi-day infusions at much higher dosages than the oral dosages in my protocol. Drexel University has treated over 3,000 patients with infusions of 40 mg/hour for 5 days with no lasting adverse effects. Even higher doses than that are used for surgical anesthesia. Ketamine is a powerful tool for treating pain.

Medical Publications


You can click and download each reference in blue below

High dose ketamine improves neurological outcome after stroke in rats, Reeker et al, Canadian J Anesth 47:572-578, 2000

Ketamine, Pasero C, McCaffery M, Amer J Nursing, 105:60-64, 2005
An excellent review, more clinical, easier to read than some more technical papers

Ketamine in Chronic Pain Management: An Evidence Based Review, Hocking & Cousins, Anesth Analg, 97(6):1730-1739, 2003This nine page article is the best comprehensive review of ketamine’s use in almost every known pain condition including post stroke pain.  Easier to read; a catalogue of pain syndromes and references.

Ketamine Stops Aura in Familial Hemiplegic Migraine, Neurology, 55:139-141, 2000 Two mechanisms may account for this. First, ketamine can increase cerebral blood flow, which may counteract the marked hypoperfusion induced by cortical spreading depression, as observed in migraine with aura. Second, in experimental animals, ketamine accelerates the  restitution of neuronal function after hypoxia.

Ketamine oral use in 8 chronic pain patients, Canadian J. of Anesthesia, 2004


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The Reflex Sympathetic Dystrophy Association library has many articles on RSD, CRPS and ketamine. Remember most of the articles are written for scientists and physicians.

From their library I particularly recommend the first article, below.  The last two are very technical but important new research.


Expectations of Pain: I Think, Therefore I Am, Jones-London M, National Institute of Neurological Disorders and Stroke

For pain mechanisms, read
Beyond Neurons: Evidence that Immune and Glial Cells Contribute to Pathological Pain States, Watkins L and Maier SF, Physiology Review. 2003;82:981-1011.

For pain mechanisms, read
Complex Regional Pain Syndrome (CRPS): Evidence of focal small-fiber axonal degeneration in complex regional pain syndrome-I (reflex sympathetic dystrophy),  Oaklander AL et al., Pain. 2006;120:235-243.

There is no link to the following double blind controlled research publication:

Mercadante S, Arcuri E, Tirelli W, Casuccio A. Analgesic effect of intravenous Ketamine in cancer patients on morphine therapy: a randomized, controlled, double-blind, crossover, double-dose study. J Pain Symptom Manage 2000;20:246-252. Mercadante et al compared intravenous infusions of Ketamine (0.25 and 0.5 mg/kg) with placebo in a double-blind, crossover study of 10 cancer patients with neuropathic pain.

Please note that the free Adobe Acrobat Reader is needed to read some references.

You can download the free reader now.

~~~~~The material on this site is for informational purposes only, and is not a substitute for medical advice, diagnosis or treatment provided by a qualified health care provider. ~~~~~