I've been using Yohimbe Fuel from Twinlab, and it seems to work quite well. I also tried Yohimbe Bark from Gaia Herbs, which my mom thinks is a good brand, and that also seemed to work. But it's an extract with an alcohol base, which might have been causing me some problems until I switched to Twinlab (headache and feeling a bit hung over). Twinlab says 400mg of bark per capsule, twice per day, which they claim is 8mg of Yohimbine (the active part of the yohimbe bark) per capsule. I do 1/4 of a capsule twice per day, so that's about 100mg of bark and 2mg of Yohimbine twice per day. Which gives me a daily total of 200mg of bark and 4mg of Yohimbine. A smaller dose might work, but I haven't tried it yet. Basically the 100mg dose isn't causing me any problems, and the stuff is dirt cheap, so I'm not worried saving cash. 4 bottles will last me over a year In the US, it shouldn't be too hard to find a doctor who is somewhat willing to investigate things. It might help to check websites for someone who likes to treat complex and chronic disease . . . autism, IBS, fibromyalgia, etc. Even if you can't find someone who knows much about ME/CFS, you might be able to find a doctor who isn't afraid of a challenge.