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Reduced Itraconazole Concentration and Durations Are Successful in Treating Batrachochytrium dendrobatidis Infection in Amphibians
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Potential interaction between itraconazole and clarithromycin

B Auclair1, S E Berning, G A Huitt

  • 1Department of Medicine, National Jewish Center for Immunology and Respiratory Medicine, University of Colorado, Denver 80206, USA.

Pharmacotherapy
|December 22, 1999
PubMed

Insights

This study investigated drug interactions between clarithromycin and itraconazole in HIV-negative patients with Mycobacterium avium complex and aspergillosis. The findings suggest these antifungals can be safely co-administered, despite potential pharmacokinetic changes.

Area of Science:

  • Pharmacology
  • Infectious Diseases
  • Drug Interactions

Background:

  • Pulmonary Mycobacterium avium complex (MAC) and aspergillosis are opportunistic infections.
  • Treatment often involves clarithromycin for MAC and azole antifungals for aspergillosis.
  • Drug-drug interactions can affect treatment efficacy and safety.

Observation:

  • Three HIV-negative patients with MAC and aspergillosis received clarithromycin and itraconazole.
  • All patients exhibited increased clarithromycin concentrations and altered metabolite ratios.
  • No clinical adverse events were reported during treatment.

Findings:

  • A potential pharmacokinetic interaction between clarithromycin and itraconazole was observed.
  • The interaction is hypothesized to involve cytochrome P450 3A4 enzyme activity.
  • Bidirectional interaction effects cannot be excluded.

Implications:

  • Clarithromycin and itraconazole may be safely co-administered when clinically indicated.
  • Further research is needed to fully elucidate the clinical significance of this interaction.
  • This finding has implications for managing co-infections in immunocompromised patients.

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