A 25 year old female, presents to the clinic with dysuria, urinary frequency and urgency. After a laboratory workup a diagnosis of cystitis is made. Which is the first line drug for the treatment for this patient?

First line agents used in the treatment of uncomplicated cystitis are Trimethoprim Sulfamethoxazole and Nitrofurantoin. Nitrofurantoin is highly effective against E coli and most non E coli isolates. Second line agents used in its treatment are flouroquinolones and beta lactam antibiotics. Commonly used flouroquinolones in the treatment of UTI are ofloxacin, ciprofloxacin and levofloxacin. Drugs used in the treatment of UTI in pregnancy are: nitrofurantoin, ampicillin and cephalosporins. Ampicillin and cephalosporins are the drugs of choice for the treatment of asymptomatic or symptomatic UTI in pregnant patients. In pregnant patients with ove pyelonephritis parenteral beta lactam therapy with or without aminoglycosides is the standard of care. Ref: Harrison's Principles of Internal Medicine, 18th edn, chapter 288