Postexposure Prophylaxis against Experimental Inhalation Anthrax
"One control animal survived the initial aerosol challenge
and appears not to have become infected, as blood cultures
were negative and an immune response never developed.
There were three deaths that were not due to anthrax. One
ciprofloxacin-treated animal died of an aspiration pneumonia,
1 animal in the doxycycline plus vaccine group died 6
days after discontinuing the antibiotic and the cause ofdeath
could not be established, and 1 animal in the ciprofloxacin
group died 73 days after antibiotic was discontinued because
of urethral obstruction due to rubbery concretions. The relationship
of the latter finding to the crystalluria induced by
ciprofloxacin in nonhuman primates  is unclear. as the
ciprofloxacin had been stopped for >2 months."