Research was published in the American Journal of Veterinary Research [March 2019, Vol. 80, No. 3, Pages 294-299, https://doi.org/10.2460/ajvr.80.3.294] on the use of dipyrone as a treatment for pyrexia in horses. The authors were Peter R. Morresey, BVSc, MVM; Gary W. White, DVM; Melinda Poole, DVM; Tianhua Hu, PhD; Ming Yin, PhD and Emily A. Sundman, DVM.
Following is information from the Abstract of this research titled "Randomized blinded controlled trial of dipyrone as a treatment for pyrexia in horses."
"To evaluate the effectiveness and safety of dipyrone to control pyrexia in horses with naturally occurring disease under field conditions."
"138 horses with pyrexia and various infections evaluated at 14 veterinary sites in 12 states."
"In the first (effectiveness) phase of this 2-phase study, horses were randomly assigned 3:1 to receive 1 dose of dipyrone (30 mg/kg [13.6 mg/lb], IV) or an equivalent amount of placebo. Effectiveness was defined as a decrease in rectal temperature ≥ 1.1°C (2°F), compared with the pretreatment value, or a rectal temperature of ≤ 38.3°C (101.0°F) 6 hours after treatment administration. Horses deemed to have an appropriate reduction in rectal temperature (regardless of treatment group) by 6 hours were immediately entered into the safety phase of the study, in which dipyrone was administered IV at 30 mg/kg between 0 and 8 times up to every 8 hours on an as-needed basis, as determined by the clinical investigators. Horses were monitored throughout for adverse events."
"A significantly greater proportion of dipyrone-treated horses (76/99 [77%]) had an effective treatment response than did placebo-treated horses (6/31 [19%]). Post-treatment adverse events were mild and transient. No differences in types or prevalence of gastrointestinal adverse events were evident between treatment groups."
Conclusions and Clinical Relevance
"Dipyrone was effective in controlling pyrexia by 6 hours after IV administration of a single 30-mg/kg dose in a large proportion of treated horses. Adverse effects were minimal."
Access to this article is available from the American Journal of Veterinary Research.