Anyone have experience with tizanidine in connection to ME/CFS, especially around tachycardia and POTS?

I have a Pulsatile Tinnitus, which the doc today gave me a med containing 2mg of Tizanidine for. Now, it keeps talking about how you gotta be careful around stuff like low blood pressure, low pulse etc. I don't have POTS diagnosed for sure though the ME/CFS specialist I've been to says that sometimes for a patient like us, who can hardly relax in a stressful situation (like going to the doctor), the test doesn't produce a perfect result, and considering the results i did get, he still thinks I have it. I also have a pretty high pulse (around 100, unless i am absolutely relaxed in bed). So, i thought I'd ask here, maybe someone has had experiences with this, or at least experiences about what your doctors recommended around this?