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Pharmacokinetics of macrolides in foals

N Villarino1, T Martín-Jiménez

  • 1Department of Microbiology, University of Tennessee, Knoxville, TN, USA.

Journal of Veterinary Pharmacology and Therapeutics
|October 23, 2012
PubMed

Insights

Macrolide antibiotics effectively treat Rhodococcus equi infections in foals. These drugs distribute extensively and persist long-term in foal lung tissues, including pulmonary epithelial lining fluid and bronchoalveolar lavage cells.

Area of Science:

  • Veterinary Pharmacology
  • Equine Medicine
  • Antimicrobial Pharmacokinetics

Background:

  • Rhodococcus equi infections, particularly pneumonia, are a significant concern in foals.
  • Macrolides are a primary treatment class for these infections.
  • Understanding drug distribution and persistence in foal lungs is crucial for effective therapy.

Purpose of the Study:

  • To review the pharmacokinetic characteristics of various macrolides in foals.
  • To emphasize drug concentrations within specific lung compartments: pulmonary epithelial lining fluid (PELF) and bronchoalveolar lavage (BAL) cells.

Main Methods:

  • Review of existing pharmacokinetic data for macrolides in foals.
  • Focus on studies measuring drug concentrations in PELF and BAL cells.
  • Analysis of pharmacokinetic profiles of erythromycin, azithromycin, clarithromycin, tulathromycin, telithromycin, gamithromycin, and tilmicosin.

Main Results:

  • Macrolides exhibit rapid and extensive distribution within foal lung tissues.
  • These drugs demonstrate prolonged persistence in PELF and BAL cells.
  • Variations in pharmacokinetic profiles exist among different macrolide agents.

Conclusions:

  • Macrolides possess unique pharmacokinetic properties beneficial for treating Rhodococcus equi lung infections in foals.
  • High and sustained concentrations in PELF and BAL cells likely contribute to treatment efficacy.
  • Further research may optimize macrolide selection and dosing strategies for foal respiratory diseases.

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