Plus-Hex CLINICAL
Table 1 . Adjunctive analgesic agents for ferrets .
Drug Dosage Comments
|
• Some excitatory reactions have been observed in ferrets [ 2 ] , possibly
Tramadol
|
5 – 10 mg / kg , PO / |
SC q12 – 24h [ 12 , 13 ] |
|
due to irritation at the injection site , with these reactions being more pronounced at higher doses [ 22 ] |
• Tramadol metabolites act primarily as μ-receptor agonists , but they also interact with κ and δ receptors . Additionally , tramadol is believed to increase levels of serotonin and noradrenaline
• Used for ongoing chronic pain
• To the authors ' knowledge , there are no studies in ferrets
Gabapentin 3 – 5 mg / kg PO , q8h [ 12 , 13 ] • γ-aminobutyric acid analogue
• Originally used as an anticonvulsant and later to treat neuropathic pain
• Used to treat chronic pain
• There is no research in ferrets
Ketamine Perioperative / postoperative analgesia : 0.3 – 1.2 mg / kg / hour CRI following a 2 – 5 mg / kg IV loading dose
Postoperative analgesia : 0.1 – 0.4 mg / kg / hour CRI [ 13 ]
• Dissociative anaesthetic and N-methyl-D-aspartate receptor antagonist , as well as influencing other receptor systems
• Works as an ‘ anti-hyperalgesic ’, and reverses or prevents central sensitisation [ 23 ] . Ketamine works synergistically with opioids , therefore reducing the dose and potential side effects of opioids
• Side effects : psychological effects , muscle rigidity and indirect stimulation of the cardiovascular system . There are reports in human medicine of an increase in liver enzyme activity following ketamine use [ 23 ]
• Combined with benzodiazepines to ‘ dampen ’ the psychological effects of ketamine [ 23 ]
• Used as part of a multimodal anaesthetic protocol , in micro-doses to manage pain peri- and postoperatively , and as a CRI ( Figure 4 , page 18 )
• Veterinary anaesthetists and pain specialists report success with monthly subcutaneous injections of low-dose ketamine ( e . g . 0.5 mg / kg ) as an adjunctive agent to manage chronic pain in cats and dogs [ 24 , 25 ] . However , to the authors ' knowledge , this is not described in ferrets
Amantadine 3 – 5 mg / kg [ 12 , 13 ] • The doses in the formularies for exotic species are anecdotal and extrapolated from the doses for cats and dogs
• Provides analgesia by acting as an N-methyl-D-aspartate receptor antagonist
• Studied in laboratory ferrets for antiviral activity in influenza studies , but to the authors ' knowledge , there is no information on its use in pain management in ferrets
Paracetamol / acetaminophen
Do not use • Toxic in ferrets , similarly to cats , due to their slow glucuronidation of this drug in the liver [ 26 ]
Ibuprofen Do not use • In ferrets , ibuprofen has a reported very narrow safety range , and ferrets are very sensitive to risk of toxicity [ 22 , 27 ] . Although therapeutic doses are anecdotally described [ 8 , 12 ] , ibuprofen is not recommended .
CRI , constant rate infusion ; IV , intravenous ; PO , oral ; SC , subcutaneous .
Volume 40 ( 1 ) • February 2025
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