Flomax
"Prescribed .4mg flowmax 1x daily for kidney stone.  Holy cow this stuff lowered my blood pressure!  Took one dose at night, and almost fainted when I awoke and tried to get up, which is a know side effect but it took 16 hours to get back to where I could walk and I was pounding liquids the whole time.  Should be more clearly designated.  My HR was up in the 110  range and my resting rate is 60 normally."