You have to be aware of a very rare, but well recognised complication - necrotising fascitis (Fournier's gangrene).
The symptoms are red raw skin or blisters in the genital/perineum region. This is a bacterial infection which requires IMMEDIATE medical attention. If left, it can be fatal.
I believe 12 cases (in the USA, I believe), has been diagnosed.
I have been on it for about a year with no real side effects, save perhaps increased urination. But the advantages (increased heart & kidney protection) outweigh the inconvenience of having to pee more often.