To : Gretchem Re : Fluroquinolone antibiotics, Phenazopyridine It seems this question will not go away, and to be truthful, it is one we don't really have a good answer for. To begin with, the fluoroquinolone family (Ciprofloxacin, Enoxacin, Lomefloxacin, Norfloxacin, Ofloxacin,trovafloxacin) are incredibly efficient for urinary tract and other gram negative infections, hence they are quite popular. But also, they have been implicated in a problem called arthropathy in which the synovium (lining of the joint) in young animals(beagle dogs) was noted to swell significantly. It is controversial as to whether this occurs in human infants. Therefore, fluoroquinolones are generally avoided in children less than 18 years of age, but they are commonly used in children with cystic fibrosis, as nothing else works after a while. Also, some pediatricians do use them when they feel the culture sensitivities require them. We have little data on their transfer into human milk. We have one report of pseudomembranous colitis in one breastfed infant of a mom who took Ciprofloxacin. Remember, pseudomembranous colitis occurs in less then 1% of cases of individuals who are taking "therapeutic" doses anyway...we don't know the rate of occurrence in "breast fed infants". We have some data on ofloxacin, norfloxacin, and trovafloxacin that suggest their breast milk levels are quite low. So I posed this question to my Pediatric Gastroenterologist who walked by, and he suggested that he would suggest the mom continue to breastfeed, and at the first sign of diarrhea, discontinue breastfeeding. I think this is a logical, common sense approach. Further, I would suggest to use trovafloxacin, or norfloxacin, as we have some data suggesting their breastmilk levels are very low and they may be better choices for the breastfeeding mother. As for phenazopyridine, I believe that it is only marginally effective as a urinary tract analgesic, and may not be worth the risk to the infant. I would not suggest its use for more than 24-48 hours before switching to other analgesics such as Ibuprofen, etc. Regards Tom Hale, Ph.D.