I take 10mg x 3/day. I noticed a decrease in blood pooling, especially in my hands. My hands used to be red and splotchy almost all day long. I notice this less now, although it still happens. The only side effects I had was scalp tingling and goosebumps about 15 minutes after taking my dose. After a few months, this stopped happening. I did not notice a chance in my weight. Midodrine is fast acting and I can definitely tell when the effects are wearing off.
Even during my worst episodes my 02 saturation has been in the high 90s. I hope your appointment tomorrow goes well and that you get some answers.