Nitrofurantoin
"I was prescribed Nitrofurantoin(7 days) after Trimethoprim wasn't working after 3 days. What started as a urine infection got further up and spread to bladder & kidneys. 
I immediately looked online at reviews of Nitrofurantoin and was scared to death about taking it after what I read. 
I took it at 8am and 8pm WITH food (just 2 slices of toast or 2 weetabix was enough for me to not feel sick after taking it) BUT for me, if I got up and tried to do too much just after taking the tablet I'd feel a bit sick. So for the first hour after taking it i'd just sit and relax and then I'd be fine!  
The only side effect I got was a bit of a dry mouth. I started feeling the tablet working after 2 days. Definitely recommend this! U.K. England"