I read a recent study that found that taking DMSA for just 3 days was able to dramatically raise low glutathione levels up to normal for at least 2 months (the duration of the study). Do you think taking DMSA for 3 days every 2 months to maintain normal glutathione levels would be a good idea to treat CFS? I read the preliminary results of the study a year ago and tried it but DMSA caused too many side-effects for me and didn't help but since we're all different I wonder whether it may help others.

The study found that 3 days of DMSA resulted in a "dramatic normalization of RBC glutathione in almost all cases." The reason it says normalized is because some participants had high levels of glutathione that decreased to normal while glutathione levels increased to normal levels in those with low glutathione.

The finding that DMSA dramatically normalizes glutathione levels was an unexpected result in a study designed to test whether DMSA is an effective treatment for autism. Do you think it would raise low glutathione in people with CFS also?

Link to study - http://www.ncbi.nlm.nih.gov/pubmed/19852789

Hi, fredt.

Sorry for the delay in responding. I have now had a chance to read the full paper. Thank you for letting me know about it.

As you noted, this result is surprising. It is known that DMSA binds cysteine and takes it out of the body. It is also known that cysteine is usually the rate-limiting enzyme for the synthesis of glutathione, so that action would be expected to lower the rate of production of glutathione.

However, DMSA also takes out mercury, and mercury is known to block several enzymes that are involved in the synthesis of glutathione, as well as upstream in the sulfur metabolism. Based on the results of this study, it appears that this action was dominant, and overwhelms the cysteine wasting action.

It was also interesting, as you noted, that those who had high RBC glutathione levels initially had their levels lowered toward normal by the DMSA treatment. The authors suggested that in these cases, glutathione synthesis had been increased in order to deal with the mercury load, and when the mercury load was decreased, glutathione synthesis dropped back toward normal.

I'm not ready to conclude yet that the periodic DMSA treatment you suggest would be a good way to raise glutathione, but it's an interesting idea. I can tell you that in the study that Dr. Nathan and I did of the simplified treatment approach, he found after the 6-month study was completed, that some of the patients did benefit from treatment to bind and take out mercury. I think he used DMPS rather than DMSA for that, though. Note that this was done after 6 months of treatment to lift the methylation cycle block and allow mercury to come up.

I know of one case in which the person had low glutathione, and did a DMPS challenge urine test for toxic metals, and this made her feel much worse for a while. So I am leery of using one of these so-called chelators that have sulfhydryl groups in a person who is low in glutathione. I realize that that is counter to the result in this study. I have heard from one of the authors of this study, and he wrote that he thinks it will be important to see if the results can be confirmed by an independent study, because he found the results surprising, too.

Another thing you might be interested in is that a paper was published in 2008 showing that mercury toxicity does effect visual contrast sensitivity. So people who have a positive result in Dr. Shoemaker's FACT test may be suffering from mercury toxicity, rather than from a biotoxin, such as from mold, Lyme, or ciguatera. To distinguish these, I think the panel of other tests he runs is helpful.

Sorry I can't be more definitive about this.

Rich

Thanks for looking at the study and responding. What confused me in the study was how a 50% increase in mercury excretion for just 3 days could raise glutathione levels so much so I thought it might be something unique to DMSA instead of getting rid of mercury as they suggested in the paper but I guess a little bit can make a big difference. It seemed odd that they used a lead chelator (DMSA) instead of a mercury chelator (DMPS) since they seemed to think mercury was the problem. I hope someone decides to research this in an independent study to see if they get the same results.

Hi, fredt.

I think that one thing that should be noted is that they measured glutathione in the red blood cells. Red blood cells are normally producers and net exporters of glutathione. The level of glutathione in the red blood cells may not have accurately reflected the level in tissue cells.

In the Vitamin Diagnostics panel, glutathione is measured in the blood plasma. I think that this reflects what's going on in the tissue cells more accurately, but it's at a much lower level in the plasma, and it's a harder measurement to make accurately.

I think there have been fewer problems with DMSA than with DMPS, so some people view it as safer.

I hope that more research will be done on this, too.

Rich

Okay. That makes more sense. Thanks for explaining.