Can the experts please talk about the most suitable antibiotic class used for urinary tract infections in general?

For women with : Occasional UTI symptoms trimethoprim/sulfa, nitrofurantoin, and Ampicillin would be some of the most common and effective. Typical length of treatment would be 3-5 days.

Depends: The best antibiotic is the narrowest spectrum, lowest side effect and least expensive drug that kills the bacteria causing the infection. A urine culture and sensitivity are nessesary to determine the proper antibiotic.