Effects of dipyrone, meloxicam, or the combination on hemostasis in conscious dogs

Abstract

While meloxicam does not alter hemostasis by the methods evaluated, dipyrone inhibits platelet aggregation for up to 3 hours. Meloxicam-dipyrone combination causes more prolonged inhibition of platelet function than dipyrone alone. Decreased platelet aggregation induced by dipyrone and dipyrone-meloxicam does not appear to impact the viscoelastic properties of the blood clot nor increase the risk of bleeding in dogs without preexisting hemostatic disorders.

Hemorrhagic, Hemostatic, and Thromboelastometric Disorders in 35 Dogs with a Clinical Diagnosis of Leptospirosis: A Prospective Study

“…Finally, 2 dogs received meloxicam before admission. These dogs were not excluded from the study, in accordance with the results of a previous study in which the administration of meloxicam did not seem to alter hemostasis according to the methods evaluated (TEM and whole blood platelet aggregation) in dogs …”

Use of a Cyclooxygenase-2 Inhibitor Does Not Inhibit Platelet Activation or Growth Factor Release From Platelet-Rich Plasma

“…Although some previous studies demonstrate impairment of platelet function with use of NSAIDs, it is also important to note that many studies fail to demonstrate an inhibitory effect of NSAIDs on platelets. 4,10,14,16,45 The same is true regarding the use of carprofen in dogs. Multiple studies have demonstrated some impairment in platelet aggregation or tissue TXB2 concentrations, 9,27,43 while numerous other studies have failed to show an effect of carprofen use on primary hemostasis, TXB2, and 6-keto prostaglandin F1a.…”

“…1,30,38 It is also possible that changes in platelet activity could be dependent on the specific NSAID studied and the species in which the study is performed, particularly as this study examined the effects of a selective COX-2 inhibitor. 10,14,35,45 As COX-1, rather than COX-2, is more instrumental in production of TXA2 from prostaglandin H 2 , the selective COX-2 activity of the NSAID used in this study may preclude it from having an effect on platelet activation and growth factor release. 2,9,28 The observation that TXB2 was not decreased with use of the COX-2 inhibitor in this study suggests that these platelets were still able to produce thromboxane, probably via the COX-1 pathway.…”

The using of a piglets as a model for evaluating the dipyrone hematological effects

“…Similar effects were found in rats [33]. In dogs, however, there was no significant MET effect in level of WBC when given at a dose of 25 mg/kg [34]. With regard to piglet model, the effect of the MET on WBC also manifests the fluctuating course of the curve reporting on the effect.…”

“…Yet, in rat-based studies, MET administration induced a slight fall in Hct [33], while in dogs, no MET-induced effects were seen in Hct levels at a dose of 25 mg/kg [34]. Of note, the observed variability is substantial, however, the observed decrease is significant ( p  < 0.05).…”