Analysis of analgesic efficiency, action on cyclooxygenases 1 and 2 and investigation of the adverse effects of the use of dipyrone or carprofen on post-operative analgesia in dogs undergoing orchiectomy

• Grant number: 15/19931-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2016
• End date: December 31, 2016
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Aline Magalhães Ambrósio
• Grantee: Karina D'Angelo Campos
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Today, pain is considered to be the fifth vital sign that must be evaluated in any patient, and it is a condition that requires treatment in each and every case, seen that there are no excuses for not controlling it. Post-operative pain deserves much attention, since it is estimated that in 5 to 80% of the improperly treated cases, post-operative pain progresses to chronic pain. Among the drugs available for managing pain, there is dipyrone, a non-opioid analgesic indicated for treating mild to moderate pain and, in association to other drugs, to achieve better analgesia and obtain lower incidence of adverse effects. However, despite being largely used in small animals, there are few studies in veterinary medicine that have investigated its efficacy and safety. Moreover, its mechanism of action remains uncertain, and there are still controversial matters regarding dipyrone adverse effects - that is the case for blood dyscrasias, which is the reason why dipyrone was banished from some countries, like the United States and Sweden. Owing to this panorama, the aim of the present study is to analyze one possible mechanism of action of dipyrone, the inhibition of the cyclooxygenase enzymes 1 and 2, through the evaluation of prostaglandin E2 and thromboxane B2 concentrations along the perioperative period in animals treated either with dypirone or carprofen. Furthermore, the present study intends to assess the analgesic efficiency of dypirone alone and compare it to carprofen, and investigate the occurrence of adverse effects associated to dipyrone after a period of 7 days of administration by monitoring the animals' hemogram and by applying a questionnaire on the owners.