When I kept getting UTIs Nitrofurantoin was the one identified as the best for the job. It has never worked for me. As for Trimethoprim - hah - that's even more useless. The thing that worked for me was Co-amoxiclav, that lasted 14 years.
However UTIs started again in 2011, I tried Nitrofurantoin for about 2 years, it would work after 2 days then infection would come back after 2 months. Eventually spoke to a sensible GP about getting co-amoxiclav again, he said that it was one of the antibs that had been identified as a match, so gave me some. This was 7 months ago, so far so good, peeing is pain free.
Doesn't take much to make me happy
Note to self - must get some acidopholos tabs
Taz how are you now?