Cipro (Ciprofloxacin Hydrochloride)
for Inhalation Anthrax

Message to Physicians and Health Practitioners on Cipro

  • Cipro (ciprofloxacin hydrochloride) is indicated for inhalational anthrax (post-exposure), to reduce the incidence or progression of disease following exposure to aerosolized Bacillus anthracis. Drug administration should begin as soon as possible after suspected or confirmed exposure to aerosolized Bacillus anthracis spores.

  • Cipro (ciprofloxacin hydrochloride) therapy should not be begun in the absence of suspected or confirmed exposure to aerosolized Bacillus anthracis. Cipro reduces the risk of severe disease following exposure, but does not prevent exposure to aerosolized Bacillus anthracis.
  • If a person is exposed to B. anthracis, the risk of adverse events caused by Cipro (ciprofloxacin hydrochloride) therapy may be acceptable because of the severity of this disease. However, in the absence of exposure, the risk of these side effects may not be acceptable.

      Possible adverse events and other concerns include:

    • CNS effects (dizziness, confusion, tremors, hallucinations, depression, increased risk of seizures)
    • Drug Interactions (Cipro may increase levels of theophylline and caffeine, other vitamin and drug products may reduce availability of Cipro)
    • Hypersensitivity
    • Pseudomembraneous colitis
    • Tendonitis/ Tendon rupture
    • Photosensitivity

  • Use of an antibiotic inappropriately (for example when exposure has not been confirmed) can lead to the emergence of resistant strains of bacteria. The usefulness of Cipro (ciprofloxacin hydrochloride) as an antibiotic may be lost if widespread use occurs.
  • The safety and effectiveness of Cipro in patients less than 18 years of age is not established except for use post-exposure in inhalational anthrax. Ciprofloxacin causes arthropathy in juvenile animals.
  • Fluroquinolones are not generally recommended during pregnancy because of their known association with arthropathy in adolescent animals and small numbers of children. However, animal studies have not shown evidence of teratogenicity related to exposure to Cipro. While there are no controlled studies of Cipro use in pregnant women to show safety and efficacy, a 1999 review of published data on experiences with Cipro use during pregnancy by TERIS - the Teratogen Information System - concluded that therapeutic doses of Cipro during pregnancy are unlikely to pose a substantial teratogenic risk, but the data are insufficient to state that there is no risk1. In addition, a 1999 consensus statement by the Working Group on Civilian Biodefense recommends that Cipro be used at usual adult doses in pregnant women for therapy and postexposure prophylaxis following anthrax exposure2.
  • For more information, please see the Cipro label PDF 

1 Friedman JM and Polifka JE. Teratogenic Effects of Drugs. A Resource for Clinicians (TERIS). Baltimore, MD: The Johns Hopkins University Press; 2000:149-150.

2 Inglesby TV, et al.  Anthrax as a biological weapon: medical and public health management. Working Group on Civilian Biodefense. JAMA 1999 May 12;281(18):1735-45.   [Erratum in: JAMA 2000 Apr 19;283(15):1963]

For more information about Cipro, please contact the Division ofDrug Information at or1-888-INFOFDA (463-6332).

Source: U.S. Food and Drug Administration