My dad was put on a 'new and improved' medication to help regulate his heartbeat - he suffers the unfortunate rapid heart beat many bypass patients have to endure the rest of their lives - because nothing else seemed to do the trick.

Unfortunately, this wonder drug caused him various other more bothersome problems. He and my mom (ultimately his decision, but she had some input) sat down and decided having a functioning thyroid and rapid heartbeat was preferable to a non-functioning one and a regular heartbeat. Or something. I can't honestly remember the issues, though I know Dad's thyroid has become another part of his body that hates him now.