Page 38 - BSAVA Guide to Pain Management in Small Animal Practice
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4  |  Chronic and osteoarthritic pain



        VetBooks.ir  Paracetamol                   especially for acute episodes of  are up. See
                                                   Chapters   and   for more information about
             Paracetamol’s mode of action is still to be
             completely described but it has peripheral and   acute pain and pharmacology, respectively.
             central actions, and is widely prescribed in   Tramadol
             humans for chronic pain, although evidence for
             e cacy is weak   unter and  erreira,   16 .    ramadol is an atypical synthetic opioid that
             Currently, there is no strong evidence to   interacts with adrenergic, serotonin and
             support the use of paracetamol in OA in dogs,   opioid receptors   ukanich and Papich,    4 .
             but it may be suitable for use as a bridging    he opioid mechanisms of action can be
             medication  between switching NSAI s  or in   attributed to both the interaction of the parent
             some cases in conjunction with NSAIDs.   compound and its metabolite mono-O-
             Paracetamol is available as a licensed   desmethyltramadol   1  at the mu opioid
             formulation in combination with codeine limited   receptor, although the production of active
             to a   day course.  he licence states it should    1 is variable between dogs and this may
             not be co administered with NSAI s; however,   explain the variability in analgesia e cacy.
             it may, as in humans, be safe to use in dogs in   Currently the evidence is weak to support its
                                                   use in dogs or cats with  A.  ollowing
             con unction with NSAI s.  he recommended   administration there is a large variability in
             dosage is    mg kg in two or three divided   uptake, particularly with the human sustained-
             doses. It is also available as an injectable   release formulation. In one study tramadol
             solution  1  mg kg over   mins . Paracetamol   has been shown to have a positive e ect in
             should be avoided in cats.
                                                   dogs with OA (Malek et al.,   1   and may be
             Steroids                              useful in some cases of chronic pain.  ramadol
                                                   can be used in cats, but administration is
             Steroids can be of use if the chronic pain has an   hampered by the seemingly unpleasant taste
             in ammatory component, but are not a   of the tablet and side e ects such as dysphoria
             commonly used  rst line treatment because of   and agitation.  he recommended dosage for
             the side e ects associated with long term use.   dogs is   4 mg kg two to four times a day and
             Paradoxically, it has also been shown that   for cats   4 mg kg twice a day.  ramadol
             steroids can exacerbate neuropathic pain in   alone is unlikely to be e cacious for treating
             some human conditions   cEwen and  alia,   chronic pain, but may be a useful drug for
               1  . A prednisolone and cinchophen   animals with chronic pain that experience a
              prednoluecotropin  combination is available for    are up.  ramadol should not be used in
             dogs with  A and can be e cacious in some   animals that have received a monoamine
             patients where other modalities have failed to   oxidase inhibitor.
             bring about an improvement. Prednisolone can
             also be e ective in cats; the lowest possible   Adjunctive treatments
             e ective dose should be used.         Gabapentin
             Opioids                               Gabapentin is an anticonvulsant drug with
                                                   antinociceptive e ects. It has been
             Long-term administration of opioids in cases of   successfully used as a  rst line treatment in
             chronic pain is uncommon because of the side   animals with neuropathic pain   rubb,   1  .
             e ects caused by these drugs  constipation,    he recommended initial dose is  .  1  mg
             anorexia, sedation, pupil dilation, euphoria .   kg two to three times a day, and gradual
             Liposome-encapsulated and sustained-release   increases in dose are less likely to result in the
             formulations, which allow for a slower release   side e ect of sedation. It can be useful in
             and fewer side e ects, may be suitable for   managing chronic pain especially in cats
             some patients and conditions. Opioids may be   unable to tolerate long-term administration of
             of use in conjunction with other modalities,   NSAI s  Robertson,    8 , and appears to be

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