In vivo, nitrofurantoin (25-100 mg/kg) reducesE. colireplication and abscess formation in the renal medulla of infected rats in a dose-dependent manner. It prevents kidney and bladder infection in rats following bladder inoculation with clinical isolates ofP. mirabilis. Nitrofurantoin also prevents alkalization of urine, as well as calculi and abscess formation, in a rat model ofP. vulgarisurinary tract infection.2Formulations containing nitrofurantoin have been used to treat urinary tract infections.