The outside of my left foot became numb after I started experimenting with L-Glutamine. Has anyone seen this? The area affected is my left foot from the pinky and 4th toe down to my cuboid bone. In other words, the whole tissue surrounding those bones.

I was taking L-Glutamine for about 5 months. About a month ago, I increased the dose because I wasn't having the same effect after I switched to a cheaper brand (Optimum). I went as high as 15-20g per day and that's when I came down with severe constipation. Then the numbness of my left foot. I reduced the dose to 5g per day but the numbness still persists so I've stopped everything. Still numb.

At first, it was numb occasionally but now, it's pretty much numb all the time. It seems to be subsiding a little bit now that I'm completely off of L-Glutamine, which is the only thing that I can pinpoint to. I'm a t2 diabetic but very well controlled (5.0-5.1 A1c) and neuropathy has not been an issue for me before.

Anyone else experience this with L-Glutamine?

The only thing I can think of offhand is that too much glutamine, could push you into too much glutamate synthesis.

Alot of glutamine is absorbed in the GI tract lining... so excess in the beginning would not be so obvious. But then once that is saturated, that glutamine would go down the pathway to
glutamate, which can be problematic when too high.

This is the biochemical genetic pathway for glutamine:
http://www.genome.jp/kegg/pathway/map/map00471.html

And this is a diagram of a synapse where glutamate is the neurotransmitter:
http://www.genome.jp/kegg-bin/show_pathway?hsa04724

One has to look at the maps for a while, to finally realize how complex the biochemical reactions really are. They typically HUMBLE me... sort of the same way looking at the stars does but only in reverse, since the Kegg pathways are internal, and not out there in infinite space!

But there is a hint, in the second link: Glutamate is involved with calcium signaling. When calcium is excessive it does cause numbness on the face...around the mouth as one effect. Your numbness may be similar.

One intervention you can try is to make sure you are getting enough magnesium either in your diet or supplemented. There is a new lotion, Morton's Epsom lotion that is really good, and you can target the foot better with it than oral. It is available at most WalMart's now for a very low price. (also on Amazon for a bit more)

http://www.mortonsalt.com/for-your-h...-epsom-lotion/

This is the Wiki on glutamate receptors:
http://en.wikipedia.org/wiki/Glutamate_receptor
Pages like this typically need more than one read.... because it is so complex, I always read them over and over (with time inbetween to let it all sink in).

Try the Morton's on the top of the foot, and along the side. The skin is rather too thick for bottom application.
Cutting back on your glutamine, avoiding MSG in foods, and trying the magnesium, may reveal a change for you.
Magnesium is a NMDA receptor antagonist, and blocks excess glutamate excitation.

Thank you, so much, Mrs. D! I've tried the Epsom salt soak for the last 2 days. Will try to track down that Epsom lotion but it is rather hard to find. Not at Target nor any drug chains. My foot is still numb but it's a kind of low-grade type of numbness. Like you're given a cortisone shot but the numbness is about to wear off and you're about to return to normal. But it's not quite normal and the numbness still lingers.

I've increased my Magnesium dose to 800mg per day and see if that helps also. Thanks again for your helpful comment. It's clear to me that 15g per day was too much.

just go to the walmart site, put in a zip code search for local store, choose closest store, then put in a search for mortons epsom lotion and it will tell you if that store has it in stock or not. if not search the next nearest store etc.

It is also on Amazon online for about $2.00 more.

Thanks guys! It's at the Suffern, NY Walmart location! In stock! I'm driving there right now so I can put it on before sleep!