postural orthostatic tachycardia syndrome
"Midodrine does not affect postural orthostatic tachycardia syndrome, you need a beta-blocker for that (I am on Propranolol) which keeps your heart from kickstarting the fainting reflex that POTS patients are very susceptible to. Midodrine saved my life, it allows me to literally get up off the floor and get on with life.  I have been on it for 10 years, it has a very short life span so I take both medicines every 3 hours. I am able to function quite well, not super-duper, but I can do most things.  If it ever is pulled off the market I will literally be going to another country."