Promising New Painkiller for Canine Cancer

A recent study (October 2013) by the University of Pennsylvania School of Veterinary Medicine has found a promising new painkiller called substance-p saporin, or SAP. It is a neurotoxin that works by selectively destroying pain-sensing nerves.

In the study, 70 dogs with bone cancer participated.  In each case, the family had chosen not to pursue amputation and chemotherapy, but instead were taking a hospice approach, looking to ensure their dogs had a high quality of life for their remaining time.  Half of the dogs received standard painkillers and half received SAP.  Owners were not told which painkiller had been given to their dog, but were asked to record their dog’s pain levels and activity.  If the owner felt that the painkiller was no longer effective, they were then told which painkiller their dog had received and were offered SAP.

The two UPenn veterinarians who ran the study, Dorothy Cimino Brown and Kimberly Agnello, found that SAP was significantly more effective at pain reduction than the standard painkillers.  In fact, within the first six weeks of the study period, three-quarters of the families whose dogs were given standard painkillers asked to be “unblinded” compared to only one quarter of the families whose dogs were given SAP.

This research is not only important for dogs, but for humans as well.  Eventually, SAP may be used for us, too.

 

5 thoughts on “Promising New Painkiller for Canine Cancer

  1. Edy

    Does SAP have any pharmacological resemblance to methadone? Bone cancer in humans has been shown to respond better to methadone than to morphine or any of the traditional pain killing meds currently utilized for cancer.

    Reply
  2. Francis Clark

    No. SAP is not like methadone. SAP “selectively destroys pain-sending nerves” whereas methadone does not. This may be why SAP is used in hospice because the host is not expected to survive and , therefore, will not “miss” the destroyed pain-sensing nerves whose function is to avoid tissue damage by warning the host with painful stimuli; ostensibly, for the shirt period of time it should take to avoid the tissue damage. In cancer, where it may not be possible to “avoid” tissue damage these pain sensing nerves lose value. Destroying them seems a viable option to enduring the unremitting pain they otherwise could cause. Methadone is just a very good centrally acting ( acts on pain receptors in the brain in the central nervous system) pain reliever. No pain reliever will ever work as good as one that destroys the “messenger” nerves. Like wearing ear muffs will not hide a dog’s bark quite like severing the nerves and muscles a dog uses to bark. Bear in mind, the limb(s) affected by SAP will be sensorily unprotected from pain due to ANY stimulus (hot, cold, trauma). So the subject needs to be monitored. Also, I do not know if SAP affects are reversible; not a concern in terminal cases.

    Reply
    1. lola Post author

      Thanks for the question, Edy, and starting this discussion. Francis, I appreciate your answer to Edy’s question. This does indeed explain why SAP would be a particularly good choice in a hospice situation. Great discussion!

      Best,

      Lola

      Reply
  3. Doug

    Our son’s faithful elderly German shepherd/Rottweiler mix “Max” has developed a terminal cancer and the only thing the poor old guy is getting now is NSAIDS ….the problem there is that Max has been using NSAIDs for so long with other health issues that I don’t imagine he can tolerate them much now at all. Is it possible for his vet to get this SAP for him? I don’t want to give my son false hope if it’s not possible…?

    Reply
    1. lola Post author

      Doug –

      It is quite possible that SAP could help. I would definitely tell your son about it and have him ask his veterinarian if that would be an option for Max. If the cancer is terminal and there is nothing else you can do, then the focus is on quality of life. To me, that means pain-free. The last thing anyone wants for their beloved dog is for them to be in pain. Please let me know what happens and what your son decides to do.

      Best,

      Lola

      Reply

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>