A pilot study of the efficacy of constant-infusion ceftazidime in the treatment of endobronchial infections in adults with cystic fibrosis

Pharmacotherapy. 1999 May;19(5):620-6. doi: 10.1592/phco.19.8.620.31525.


Study objective: To compare the efficacy of constant-infusion ceftazidime (CTZ) with that of traditional intermittent dosing in a pilot trial.

Design: Prospective, crossover trial.

Subjects: Five adults with cystic fibrosis requiring intravenous antibiotic therapy for pulmonary exacerbations of the disease.

Interventions: Patients were initially treated with standard CTZ 2 g 3 times/day for 10 days. At the next hospitalization patients were crossed over and CTZ was administered as a constant infusion at a rate determined to achieve a serum concentration 6.6 times the minimum inhibitory concentration (MIC) of the least susceptible Pseudomonas aeruginosa isolate.

Measurements and main results: The pharmacokinetics of CTZ were determined, as were MICs for all P. aeruginosa isolates. Outcome parameters of interest were changes with therapy in white blood cell count, P aeruginosa density in sputum, and pulmonary function test results. Differences in these parameters for the two forms of administration were not significant. With the exception of one patient who received 6 g/day with both regimens, the average reduction in dosage with the constant infusion was 50%.

Conclusion: These preliminary data suggest that constant-infusion CTZ may be as safe and efficacious as intermittent dosing.

Publication types

  • Clinical Trial
  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Bronchial Diseases / drug therapy*
  • Ceftazidime / administration & dosage*
  • Ceftazidime / pharmacokinetics
  • Cephalosporins / administration & dosage*
  • Cephalosporins / pharmacokinetics
  • Cross-Over Studies
  • Cystic Fibrosis / drug therapy*
  • Female
  • Humans
  • Infusions, Intravenous
  • Male
  • Microbial Sensitivity Tests
  • Pilot Projects
  • Prospective Studies
  • Pseudomonas aeruginosa / drug effects
  • Pseudomonas aeruginosa / isolation & purification
  • Respiratory Function Tests
  • Respiratory Tract Infections / drug therapy*


  • Cephalosporins
  • Ceftazidime