Uncomplicated UTI 125 mg bid. Resp tract infections 250-500 mg bid. Childn >3 mth 125 mg bid or 10 mg/kg bid to a max of 250 mg daily. Childn >2 yr (w/ otitis media) 250 mg bid or 15 mg/kg bid to a max of 500 mg daily. Uncomplicated gonorrhea 1 g as single dose. Concomitant probenecid 1 g may be administered.