Highlights From the Talk

Dr De Meirleir believes metabolic dysfunction plays a key role in the pain found in ME/CFS.

Dr De Meirleir believes metabolic dysfunction plays a key role in the pain found in ME/CFS.

In this fifth video of ME/CFS Associations ‘Expert Science’ series, Dr .De Meirleir looked at why he believes pain is so common in ME/CFS and what can be done about it.

He noted that fatigue usually comes before pain in this disorder and as with sleep  cites the cytokines as major players in symptom  production but this time he points to IL-1, a proven pain inducer in animal and human studies.

De Meirleir has been increasingly focused on the gut. Instead of the viruses we hear so much about, De Meirleir tagged bacteria and, in particular, the bacteria in our guts, and the neurotoxins they produce as major factors in pain production.  How does he know this? First hand experience; antibiotic use (probably Xafaxin) results in less pain in some of his patients.

The gas nitric oxide also contributes to pain and  reducing nitric oxide levels has resulted in less pain in some of his patients.

Problems with our endogenous opiate receptors; ie those receptors found in the brain, spinal cord and gut that respond to opioid drugs, also play a role.  (Studies indicate that ‘filled’  opioid receptors in many fibromyalgia patients prevent them from responding to opioids.)  De Meirleir mentioned, encouragingly that an English group is working on altering  opioid receptor activity to reduce pain.

Lactic Acid

Levels of lactic acid high enough to suggest ME/CFS patients have been running a marathon, are not uncommon in his patients. (Lactic acid study results, unfortunately, have been inconsistent but Staci Stevens work (pers. Communication)  indicates a subset of high lactic acid producers is present.) It’s not just the muscles, though;  low oxygen levels in the gut have made a home for anerobic loving bacteria (there’s that low oxygen again) to produce high levels of lactic acid in the gut as well.

Whacky Blood Circulation and Autonomic Nervous System Dysfunction  at the Heart of the Problem

Metabolic dysfunctions  caused by poor oxygen deliver to the tissues and organs and by mitochondrial problems are  the biggest factor in creating pain in De Meirleir’s book.

Unfortunately, the biggest part of the pain process in ME/CFS is also the most difficult to treat; artificial means (supplemental oxygen?) can be applied but altered sympathetic nervous system (SNS) activity that expands the large blood vessels also shuts down the small blood vessels, resulting in, he believes, a chronic oxygen shortage not only in many organs but also in the peripheral (ie body) nerves.

This strange blood flow pattern, the big blood vessels getting too much blood, and the small ones getting too little, he believes, is  at the heart of both the metabolic and nerve pain ME/CFS patients suffer from.

Dr. DeMeirleir did not talk about pacing but given the metabolic issues present it and exercise are  clearly  critical elements of any treatment plan. De Meirleir has examined the pain/exercise interaction before.

He was one of the first researchers to find reduced exercise capacity in ME/CFS and developed easy way of predicting VO2 max using peak oxygen uptake. He proposed immune dysfunctions and nitric oxide played key roles in limiting exercise in 2005. ‘Catastrophizing’ was associated with reduced activity and body pain  and was explained at least somewhat by  increased pain and oxidative stress levels  after exercise in another.   The authors suggested rigorous pacing (and pain neurophysiology education (?)), which brings us to a story…

Interlude – Living Within Your Metabolic Limits

I just got off the phone with someone with ME/CFS who’d received some surprising  exercise test results at  the Pacific Fatigue Lab in Stockton, California.  Labeled an overachiever, she was rather shocked to learn that her body went into anerobic energy metabolism at a mere 100 heartbeats per minute, something she could easily achieve by loading the dishwasher or climbing the stairs.


  • A quirky metabolism is the biggest pain producer in ME/CFS
  • Sympathetic nervous system problems restrict blood flows to the small blood vessels causing oxygen debt in the tissues
  • Low oxygen conditions in the gut can also allow anaerobic bacteria to produce neurotoxins
  • Lactic acid accumulations in the muscles and the gut can also contribute
  • Nitric oxide reducers, probiotics, gut antibiotics and pacing can all help

Not wanting to become deconditioned and subject to the health issues that problem causes she’d always  preferred to exercise every now and then and suffer the consequences for, what she thought was, the greater good.  Her test results suggested she was hammering her system pretty hard by doing that and her  exercise protocol, developed by Staci Stevens required her to do less… much less.

After 4 weeks of  keeping within her metabolic limits, she reported she was feeling better than she had in years; she had more energy, she was  calmer and less irritable, her gut problems had vanished and her quality of life was much improved.

All it took was keeping her heart beat under 100 beats per minute and taking needed breaks. (Breaks are necessary even when keeping the heart rate below 100).


So what do we have here to reduce pain?  Not opioids but pacing, rebalancing the gut flora and nitric oxide reducers.

  • Pacing (not explicitly mentioned)
  • Certain antibiotics (probably Xafaxin) – to reduce the anerobic flora producing lactic acid
  • Probiotics – to do the same
  • Nitric oxide reducers

Not Part of the Package

Interestingly, despite the metabolic dysfunction and mitochondrial problems involved,  Dr. DeMeirleir did not suggest  mitochondrial energy enhancers (COQ10, D-Ribose, NAC, methylation protocol) or antioxidants, or given the blood circulation issues, drugs  that effect sympathetic nervous system functioning or blood volume enhancers.   De Meirleir’s early interest in  neurotransmitters and exercise (he’s an exercise physiologist by training)  did not lead him to suggest ways to effect neurotransmitter levels. Nor did he mention pain neurophysiology or pacing (heart rate monitor use?) or ways to avoid catastrophizing or depression which his latest study (he was the senior author) suggests does contribute to, even if it doesn’t cause, pain in ME/CFS.

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