Urinary antibacterial activity of fosfomycin and nitrofurantoin at registered dosages in healthy volunteers

Abstract Given emerging uropathogen resistance to more recent antibiotics, old antibiotics used for uncomplicated urinary tract infection (UTI) warrant reexamination. We investigated the urinary antibacterial activities of fosfomycin and nitrofurantoin by determining the urinary inhibitory titer (UIT) and the bactericidal titer (UBT) against uropathogens in urine samples from female volunteers after the administration of single-dose fosfomycin (3g) or nitrofurantoin (50 mg q6h or 100 mg q8h). Urine samples were collected over 48h (fosfomycin) or 8h (nitrofurantoin) with drug levels quantified with every void. Fosfomycin concentrations ranged from