Stephanie,
We have some info on Mestinon on our treatment Health Page:
http://www.medhelp.org/health_pages/Neurological-Disorders/Dysautonomia-Treatments/show/171?cid=196
We have definitely had some community members who have been on it, though there's so many of you guys that I'll admit I'm not sure who is active currently who might be taking it or have taken it in the past. I have not personally taken it but I can tell you a little bit more about it from what I've heard from other people who have:
Basically, like any other dysauto med, for the people it works well for they're ecstatic and for the people who can't tolerate the side effects, they don't care for it and stop taking it. LOL I will say that the potential side effects of Mestinon are a little more ... I'm not sure what the right word is, but ... maybe troublesome? ... so this is (I believe) one of the reasons why it is not usually one of the first-line medications tried in dysautonomia. However, that being said, I know of MANY dysauto patients who have not had success with the first-line treatments who have tried Mestinon.
For those that it works well for, it has some very distinct advantages, even over "tried and true" Midodrine and Florinef. It increases upright BP *without* increasing supine BP, so there's not that worry about supine hypertension, which is very helpful for some patients! Also, as some patients have problems with gastroparesis, Mestinon can help with the symptoms of delayed gastric emptying! So far as my personal hearsay goes, when it comes to side effects, I've heard of people having unpleasant side effects which caused them to discontinue the medicine and look for something else, but nothing dire like a terrible drug reaction or anything.
Oh, I did want to mention ... when I talked to my cardiologist early on in my illness (many moons ago, LOL) about my cognitive symptoms, he did not think they were associated with my autonomic dysfunction. Now, let me preface this with the fact that I LOVE my cardiologist and I think he's very knowledgeable about some aspects of my condition ... BUT ... when I got heavier into actually researching dysautonomia in actual medical textbooks and reading more and more journal articles I found that he'd been mistaken. One component of the symptoms from orthostatic intolerance is from cerebral hypoperfusion (reduced oxygenation of the brain tissue). This is the part that accounts for the cognitive symptoms. In fact, you can be getting reduced cerebral perfusion when upright EVEN IF YOUR BLOOD PRESSURE IS READING "NORMAL" WHEN TAKEN ON YOUR ARM. What is going on in your head and what is going on in your arm do not necessarily match at a given point in time. (Anyone who has felt sick as a dog, only to be shocked to see their machine tell them they are fine already knows this, right?!)
I do have at least one (probably a few) journal articles on blood velocity in the brain that help explain this, but they're not just full of medical jargon ... if I recally correctly they're also a little math intensive. If anyone wants them anyway, I can see if I can dig them out. I really need a secretary that could put these all in an index for me, hahaha.