Only taking NSAIDs is not effective in treating nonadaptive pain
There are no medications approved in North America for the treatment of long-term maladaptive pain in cats, and only one NSAID (meloxicam) is approved for long-term use in some parts of the world. Although recent data suggest that NSAID treatment can partially reverse central plasticity, it is generally accepted that maladaptive pain responds poorly to NSAID treatment. Additionally, concerns about the potential side effects of NSAIDs have led to research into alternative drug treatments.
Treatment strategies with other drugs
Drug selection is based on human clinical experience or the types of drugs that play an essential role in rodent models of nonadaptive pain. Recommended medications for treating maladaptive pain in cats include gabapentin, tramadol, amantadine, amitriptyline, tapentadol, flupirtine, and anti-nerve growth factor antibodies.
Based on the current clinical status, this article focuses on five types of drugs commonly used to treat chronic pain in cats:
1. Potential therapeutic drug: Gabapentin
Gabapentin acts on calcium channels, causing a decrease in calcium ion influx by binding to subunits, ultimately reducing neuronal excitability. The drug was derived from clinical experience with the use of gabapentin to treat neuralgia in human medicine and is recommended for the treatment of neuralgia in veterinary patients.
2. Potential therapeutic drug: tramadol
Tramadol is an opioid that works through several different mechanisms of action, and in human medicine, it exerts its primary analgesic effects through the action of opioids. Tramadol helps relieve the nonadaptive part of chronic pain. However, because cats are resistant to oral administration (presumably due to the bitter taste of the drug), compound preparations or improved preparations may be needed clinically.
3. Potential therapeutic drugs: amantadine
Blocking these receptors with amantadine and NMDA antagonists can prevent the development of central plasticity and treat disease in sick animals. The mechanism of action of amantadine makes it a favorable candidate for evaluating analgesic efficacy in cats. However, there needs to be more clinical data demonstrating the effectiveness of amantadine.
4. Potential therapeutic drug: Amitriptyline
Amitriptyline exerts analgesic effects in the treatment of interstitial cystitis, a bladder disorder associated with chronic neuropathic pain, and is commonly used to treat neuropathic pain.
5. Potential therapeutic drug: Maropitant
Maropitant is a central and peripheral antiemetic in the SP/NK-1 pain pathway. The evaluation of the analgesic effect of this drug has become a significant research direction.
Conclusion
Although maladaptive pain in cats is a growing concern, assessment and measurement of this pain remain challenging, hampering the evaluation of the efficacy of putative analgesics. Therefore, the treatment of chronic pain in cats remains a challenge, with only extensive clinical evaluation of the long-term analgesic efficacy and safety of NSAIDs currently available. However, some drugs have received attention for their mechanisms of action in the treatment of maladaptive pain, including gabapentin, tramadol, amantadine, and others. However, more data on the pharmacokinetics and pharmacodynamics of these drugs in cats are needed to guide treatment.