Thanks for your query.Based on the facts that you have posted it appears that you had UTI and was prescribed Niftran
(Nitrifurantoin) and got satisfactory resuts .
You have recurenceofUTI .Nitrofurantoin
is an urinary antiseptic and has to be taken for long time 3-4 weeks to have good results and to avoid recurrence of infection.
Please continue taking it safely for 2 more weeks.