So, POTS… yeah, it pretty much sucks. This one is my newest chronic invisible illness, and has been the most debilitating by far. Postural orthostatic tachycardia syndrome is a complicated beast. POTS is a type of dysautonomia, which is a malfunction of the autonomic nervous system (the part of your nervous system that controls everything involuntary, like blinking, breathing, heart rate, blood pressure, etc). As you can imagine, the autonomic nervous system malfunctioning is not a good thing. Now, let’s explain the rest of this POTS thing the best that I can.