I often get the effect, after sitting down for as short as an hour, of getting up and suddenly feeling like I will pass out. So much blood appears to rush to my head that my hearing goes, my ears and head feel like they are going to explode, and I get the pulsatile tinnitus for a few seconds. I also have these attacks in my sleep. Tonight was my worst attack and it left me with a bit of low frequency hearing loss, and I don't know if that will happen again. As a first, I was not diagnosed with OH in my recent checkup and only have low normal blood pressure. The latter possibility has not been ruled out. I am also fairly sedentary and can only do light walking as a form of exercise, which may contribute to what is going on now. Anyone else with pulsatile tinnitus suffer from either of these conditions? Any help is appreciated, thank you!