A total of 31 sexually active premenopausal women, prone to have recurrent
urinary tract infections but who otherwise were healthy, underwent postcoital prophylaxis consisting of a single oral dose of 250 mg.
cephalexin. While 127
urinary tract infections occurred in these patients during a mean of 6 months before treatment, only 1 occurred during a mean of 12 months after postcoital
cephalexin prophylaxis. This difference was statistically highly significant. Each of these patients ingested approximately 120
cephalexin tablets per year of postcoital prophylaxis. Postcoital oral
cephalexin prophylaxis is highly effective in the prevention of recurrent
urinary tract infection in the nonpregnant as well as pregnant premenopausal women because of easy compliance, the high urine concentration achieved and the minimal induction of resistance to
cephalexin in the introital gram-negative bacterial flora. Postcoital
cephalexin prophylaxis achieves identical results to daily
cephalexin prophylaxis but uses only a third of the
tablets required in the daily regimens. Finally,
cephalexin represents an additional valuable antibacterial
drug in postcoital prophylaxis along with
cotrimoxazole,
nitrofurantoin and
cinoxacin.