urinary tract infection
"Was prescribed two pills per day for seven days.  I could already tell about 5 hours after I took my first dose that my UTI symptoms had improved.  Not miraculously, but enough to give me some relief.  I went and got some Azo too, but ended up not needing to take it because the Bactrim started to help pretty quickly.  I've taken three doses now, and my symptoms are MUCH improved.  I will of course continue the full course to make sure the infection is knocked out completely.

I haven't really experienced any side effects at all.  I think if you follow the instructions to a "T" you will have much fewer, if any, side effects.  Take the pill with a meal and at least one full glass of water, then water all day long.  It works!"