Spironolactone
"I'm a 46 year old female and have been on spironolactone for 2 years for high blood pressure.  After a year and a half my doctor took me off for a couple of months as I had great blood pressure and he thought with my avid exercising and diet changes I'd be able to regulate it myself.  My blood pressure immediately shot up to dangerous levels and I had to be back on Spironolactone immediately which also immediately took my blood pressure back down to safe levels.  Unless something else comes along, I guess I'm on it for life.  I count my blessings, it does it's job and with only two noticeable side-effects for me both negative and positive:  slight drowsiness and keeps any water retention at bay (which I had a problem with previously)."