My experience on Spiro was good overall but after 18 months I started having some issues with my bloodwork. Since I knew by that time I wasn't going to stop transitioning, I took alternative actions mentioned by Laura in reply #10 and stopped the Spiro.
The most common issues that I know of among my friends are:
1. Falling over at least once. You have to stay hydrated at all times, or your blood pressure will drop when you stand. It's not hard to remember to stay hydrated since the Spiro makes you pee more, but you have to stay attuned to your body and drink when it tells you to. Usually you need to fall down at least once to learn that this isn't something that only happens to other people.
2. You'll probably never have an unbroken night's sleep while you're on Spiro. For those 18 months I was up at least once a night to pee.
3. You'll suddenly start eating pickles. Your body craves the brininess of pickles, capers or olives. I didn't even notice that I had started buying a jar of pickles a week until I got off Spiro.
4. I and many of my friends noted the decreased libido as a positive thing. I felt less like I was being run by my body and more like I was in charge. YMMV
