Dose titration of the clinical efficacy of intravenously administered flunixin meglumine in a reversible model of equine foot lameness.

The research article pertains to an experimental comparison of the efficacy of various dosages of drug flunixin meglumine (FM) in alleviating lameness in horses. The study hypothesizes and confirms that higher doses of FM have better effectiveness, but the clinical effect of double-doses is not significantly more than single doses.

Objective and Methodology

• The objective of this experiment was to study the analgesic effectiveness of different doses of Flunixin meglumine (FM), a nonsteroidal anti-inflammatory drug used to manage inflammation and pain in horses. Previous studies regarding dosage effectiveness are lacking in control references.
• The researchers expected that higher doses would have a more prominent analgesic effect in comparison to lower doses.
• The hypothesis was tested on 10 horses with induced lameness. The lameness was caused by an adjustment to the horses’ footwear that put strain on a certain part of the foot.
• After lameness induction, treatments were administered intravenously. The horses were either treated with FM in various dosages (half, single, double doses) or given a saline solution as a negative control. The order of treatment was randomized.
• Heart rate and lameness scores were monitored for 13 hours, starting one hour after lameness had been induced.

Results

• The half-dose FM showed a reduction in heart rate and lameness score at various intervals. It was significantly more effective than the saline treatment, but its effect tapered off sooner than the higher doses.
• Single and double-dose FM showed a consistent reduction in the heart rate and lameness score for up to 12 hours post administration.
• There was no significant difference between the effect of single and double-dose FM, suggesting a dose-dependent efficacy only up to a certain point.
• The concentration of FM in the plasma also varied with dosage, again showing a dose-dependent relationship for up to 6 hours post administration.

Conclusion

• The study confirmed that the administration of FM has a dose-dependent effect on lameness in horses. However, the effect does not proportionately increase beyond a certain dosage, indicating no significant advantage to using double-doses over a single dose.
• The researchers advise veterinarians to consider that while half-doses are less effective, double-doses do not provide a comparably higher clinical benefit and could potentially increase toxicity.