The macrolide antibiotics: a pharmacokinetic and pharmacodynamic overview

R Jain1, L H Danziger

  • 1University of Illinois at Chicago, College of Pharmacy (MC 886), Dept. of Pharmacy Practice, 833 S. Wood Street, Rm 164, Chicago, IL 60612, USA.

Insights

Macrolide antimicrobials, used for respiratory infections, concentrate in lung tissues more than serum. This review covers pharmacokinetic and pharmacodynamic properties of key macrolides like azithromycin and erythromycin.

Area of Science:

  • Pharmacology
  • Microbiology
  • Infectious Diseases

Background:

  • Macrolides are a class of antimicrobials with similar structures and mechanisms of action.
  • They exhibit variations in pharmacokinetic parameters and spectrum of activity.
  • Macrolides accumulate in tissues, particularly epithelial lining fluid and host defense cells like macrophages and polymorphonuclear leukocytes (PMNs).

Purpose of the Study:

  • To review the pharmacokinetic and pharmacodynamic aspects of clinically relevant macrolides.
  • To highlight the utility of macrolides in treating respiratory tract infections.

Main Methods:

  • Literature review focusing on pharmacokinetic and pharmacodynamic data.
  • Analysis of tissue and serum concentrations of macrolides.
  • Comparison of macrolide properties.

Main Results:

  • Macrolide concentrations in respiratory tract tissues and extracellular fluids are generally higher than serum concentrations.
  • This tissue accumulation enhances their efficacy for respiratory tract infections.
  • Key macrolides reviewed include azithromycin, clarithromycin, dirithromycin, erythromycin, and roxithromycin.

Conclusions:

  • Macrolides demonstrate favorable pharmacokinetic profiles for treating respiratory infections due to tissue penetration and accumulation.
  • Understanding these PK/PD aspects is crucial for optimizing macrolide therapy.
  • Further research into specific macrolide properties can guide clinical application.

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