Wednesday, November 15, 2006

Is DMSA/Succimer use in the absence of high lead a dangerous experiment? BC on Autism Ep 23


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A recent paper caught my eye since it claimed that the use of the chelation agent, DMSA/Succimer, may contribute to cognitive deficits if used in the absence of lead contamination of an animal model.

This is a good paper, but I'm just not entirely convinced the the data. Dunno, maybe it's just me. The bottom line is that if one is convinced by their data that succimer treatment can alleviate lead-induced cognitive deficits, then I believe that one has to be convinced by their data that succimer treatment in the absence of lead contamination induces cognitive defects itself - that's a huge and scary statement.

Check it out.

Formats available: Quicktime (.mov)

7 Comments:

At 11/16/2006 8:39 AM, Blogger notmercury said...

Very nice. Thanks for breaking it down in easy to understand language.

So the difference in cognitive performance was marginal between groups but I guess when that's compared to the sort of cognitive deficits attributed to human lead exposure, the effect is subtle enough that it requires a large population wide analysis to reveal a relatively small decrease in IQ points.

It's very interesting to me that the Pb(-) sux exposed group experienced cognitive declines since autism is not lead poisoning. Therefore it's entirely possible that chelation therapy is doing more harm than good but we would have no way of detecting this without a well controlled study.

So many parents report a negative response to chelation you have to wonder if the gains they see aren't simply a bounce back from the neuro-inhibitory effects of the chelation agents. Makes me ill to think about that possibility.

 
At 11/16/2006 9:24 AM, Anonymous Anonymous said...

Succimer studies on lead exposed children have not come up with any significant cognitive differences between placebo- and succimer-treated groups. But that could be either because the children did have a moderate burden of lead, or because the impairment caused by DMSA is not detectable. One of the studies did ask the question as to why reducing levels of lead in children did not result in cognitive gains. They speculated it might be because succimer could also be causing cognitive impairment, but they said that's an unlikely possibility.

Now, the studies that are being conducted with autistic children are done with groups of kids who in average do not have even a moderate burden of lead (or any other heavy metal) as far as is known. Hell will break lose if they report such adverse effects. The NIHM could easily get sued for conducting the study in the first place.

 
At 11/16/2006 12:06 PM, Blogger Bartholomew Cubbins said...

I just can't even believe that this hasn't been worked out prior to the NIMH study.

NM said, "Therefore it's entirely possible that chelation therapy is doing more harm than good but we would have no way of detecting this without a well controlled study."

That is the nightmare scenario.

Joseph said, "The NIMH could easily get sued for conducting the study in the first place."

My hope is that they're more worried about the kids than lawsuits and I'm a bit shocked that the worry for the kids' safety didn't raise up a big red flag in meetings when they decided to go and do that study.

 
At 11/16/2006 12:09 PM, Blogger Bartholomew Cubbins said...

In a private email with someone who has extreme cognitive and typing abilities, the point of Fe depletion was brought up. That's another worry.

Just as I brought up with EDTA, I am unaware of any kinetic studies of the interactions between metals and succimer. That they don't exist or aren't known by those who use them, in and of itself, is a travesty.

 
At 11/16/2006 2:52 PM, Blogger Bartholomew Cubbins said...

argh. It was pointed out via email that I typo'ed DMSA and DMPS - sorry I was juggling one too many papers and rushed to get this out. It's fixed on the page here but there's no way I'm going to fix the vid.

thanks.

 
At 11/30/2006 11:50 AM, Anonymous Anonymous said...

There are also data from non-human primates which supports this rodent research that Succimer itself can be neurotoxic if used in the absence of heavy metal exposure.

Annette Nov 30, 2006

 
At 11/30/2006 8:18 PM, Blogger Bartholomew Cubbins said...

Thanks Annette, it makes perfect sense to me that a real chelator, if it works properly in the body, will do exactly what it's supposed to do: chelate a metal and improve its excretion from the body. What happens if it binds iron and starts depleting it? Not good. Real chelators aren't something to dabble in - it's a real drug.

 

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