Thanks for all your feedback so far! I definitely see some potential problems with this approach (cost, sensitivity of the results to other factors, etc.), but I still think I'll get my Mom to try it 2 or 3 times over the next 6 - 18 months to see if it's useful. Obviously, since there is not a lot of literature on this topic, I will have to "interpret" the results carefully and critically. By all means, I will share any insight and data that I get out of it for others to see.

Again, I still think there could be value in this approach if you find that, for example, in all 3 tests your norepinephrine levels were very low... or very normal. I think this is good information to have ... we may be surprised in what we find, which could affect our choice in treatment ... or we may get nothing out of it. To me, it's worth a try since measuring is a fundamental part of the scientific method.

A couple of additional thoughts I've run across in researching this ... you can form your own opinion about the validity ...

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Some concern over mail-order urine approach to measuring NT levels:

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I plan on trying the blood platelets-based test from Vitamin Diagnostics lab in New Jersey (referenced the Julia Ross link above).
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