I convinced my GP to let me try Mestinon about 18 months ago, but never got as far as actually trying it until now. I have been holding off because I didn't want to muddle the results by starting it too close to my last rtx dose or while I was starting out on LDN. While LDN is extremely helpful in reducing pain and the intensity of PEM, POTS or OI of some sort are among my more debilitating symptoms, so I'm hoping that Mestinon might help even just a little bit. Seeing as I'm spending most of my time in bed atm, any increase in activity should be easy to spot. I will be tracking activity levels and HR every day using my Polar HR monitor and my Oura ring (I do that anyway). Starting carefully on just 15 mg to make sure that I tolerate it and will build slowly from there. I've started this thread to track this n=1 trial Feel free to share your own experiences with Mestinon here, or anything else that might be relevant. DAY 1: 15 mg. Feeling a little bit jittery, but that could just be the coffee. Will report back in a week or so, or whenever there is something to report.