Adjuvant analgesics – Alternatives to opioid analgesia : ALPHA-2 AGONISTS
DOULEUR CHEZ LES CHIENS ET CHATS
1/ Adjuvant Analgesics in Acute Pain Management
Hélène L.M. Ruel, DMV, MSc, Paulo V. Steagall, MV, MSc, PhD*
- Theefficacyofgabapentinincombinationwithbuprenorphinehasbeendemonstratedaf- ter ovariohysterectomy in cats. Additional studies using gabapentin alone are required to evaluate its efficacy in dogs and cats.
- The use of ketamine in clinical practice, including dosage regimens, drug combinations, advantages, disadvantages or limitations, anesthetic-sparing effects, and clinically rele- vant studies, is presented.
- The analgesic efficacy of tramadol relies on the activity of cytochrome P 450 enzymes to produce its active metabolites (ie, O-desmethyltramadol). Dogs produce less concentra- tions of this metabolite and tramadol’s efficacy has been questioned in this species.
- The use of tramadol in dogs should be judicious. Veterinarians should know the potential for analgesic failure and the clinical limitations of the drug in pain management.
2/ Alternatives to Opioid Analgesia in Small Animal Anesthesia: Alpha-2 Agonists
Alexander Valverde, DVM, DVSca,*, Alicia M. Skelding, DVM, MSc, DVScb
- The sedation induced by alpha-2 agonists confounds the interpretation of analgesic ef- fects but is also a part of the general analgesic effect that involves supraspinal and spinal mechanisms.
- Low systemic single doses can minimize sedative effects and provide analgesia, but it tends to be of short duration.
- Alternatively, specific administration of low doses at the site of action (eg, spinal cord)can provide analgesia of longer duration with minimal sedation.