This sounds like one of the new quinolones, like norfloxacin and
ciprofloxacin.

The first question is "Why the hottest, newest, likely most expensive
drug?" Answer: Likely, because the physician just got a visit from the
company rep.

The second question:  "Will something else do?"  The answer is almost
certainly "yes". It depends what is being treated, and this was not
mentioned in the post.

The third question:  "Will a drug from the same family do?"  The answer
is yes.  Norfloxacin and ciprofloxacin (though Dr. Hale does worry about
a report of one case of pseudomembranous colitis in a breastfed baby
whose mother took ciprofloxacin) are safe while breastfeeding.

The fourth question: "Is this drug safe while breastfeeding?"  The
answer is, given the risks of formula feeding--probably yes.  I don't
have any information about this medication.

Jack Newman, MD, FRCPC