Pharmacokinetic analysis of topical tobramycin in equine tears by automated immunoassay.

Authors: Czerwinski Sarah L, Lyon Andrew W, Skorobohach Brian, Léguillette Renaud

Journal: BMC veterinary research

DOI: 10.1186/1746-6148-8-141 PubMed: 22909398Log in to save

Summary

# Editorial Summary: Topical Tobramycin Pharmacokinetics in Equine Tears Antimicrobial selection for equine ocular infections typically relies on clinical experience rather than evidence-based dosing regimens, creating a significant gap in our understanding of drug efficacy at the site of infection. Czerwinski and colleagues used automated immunoassay to measure tobramycin concentrations in tear samples from clinically normal horses following topical application of 0.3% solution, establishing the first pharmacokinetic profile for this commonly prescribed ophthalmic antibiotic in equines. The research provides quantifiable data on tear drug concentrations over time, enabling practitioners to make informed decisions about dosing intervals and therapeutic efficacy in infectious and inflammatory conditions. These findings are particularly valuable for farriers and veterinarians managing corneal ulceration and bacterial keratitis, where appropriate antibiotic penetration and maintenance of therapeutic tear concentrations directly influence healing outcomes and reduce the risk of antimicrobial resistance. Understanding the actual pharmacokinetics of topical antibiotics in equine tears moves the profession away from empirical treatment towards evidence-based protocols tailored to the unique physiology of the equine eye.

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Practical Takeaways

•This study provides evidence-based dosing guidance for topical tobramycin in horses, moving away from empirical use to scientifically-informed ophthalmic antibiotic therapy
•Automated immunoassay offers veterinarians a reliable analytical tool for monitoring antibiotic concentrations in equine ophthalmic cases when clinical response is uncertain

Key Findings

•Topical tobramycin 0.3% achieves measurable tear concentrations in horses, enabling pharmacokinetic characterization of ophthalmic antibiotic delivery
•Automated immunoassay provides a practical method for measuring tobramycin concentrations in equine tear samples

Conditions Studied

ophthalmic infections requiring topical antibiotic therapy

Related References

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