Chapter 19 The Prevention and Management of Pain in Canine Patients 491Tips for use
The molecule is distantly related to heparin and
should be administered cautiously in patients
with known bleeding dyscrasias; some clini-
cians discontinue use prior to surgical proce-
dures. Common off‐label applications include
chronic use and administration via the subcuta-
neous route allowing it to be dispensed for
administration at home; this improves accept-
ance by decreasing cost and inconvenience.
Other investigative drugs and targets
● Capsaicin (resiniferatoxin (RTX); Adlea™)
is used as a neuroablative in humans with
intractable pain conditions (Karai et al.,
2004). Some work with this modality has
also been done in dogs with osteosarcoma
(Brown et al., 2005) and may provide an
additional utility in the future.
● Cannabinoid receptor agonists. Centrally
located CB2 receptor activity elicits hypoal-
gesia, and efforts are underway to produce
a selective molecule with demonstrable effi-
cacy without psychotropic effect. This
modality holds promise in dogs, but it is
difficult to recommend despite increasing
availability of medicinal and recreational
marijuana until more data are available in
this species.
● Substance P/neurokinin‐1 (NK‐1) antago-
nists. Maripotant (Cerenia®) is an antiemetic
approved for use in dogs, and was found to
have outcomes equivalent to pre‐anesthetic
morphine in dogs undergoing ovariohyster-
ectomy (Marquez et al., 2015). However, this
molecule failed in human trials as a pain‐
modifying agent and its true analgesic effect
in dogs remains uncertain.
● Glial inhibitors: minocycline, +‐nalaxone,
and ibudilast have glial inhibitory effects.
Glial inhibition may become an essential
adjunct to opioid therapy to minimize toler-
ance, reduce adverse effects, and enhance
potency.
● Anti‐nerve growth factor (NGF) antibody.
NGF contributes to hypersensitization and
upregulates in chronic pain. A pilot study
using an injectable canine‐specific anti‐NGF
monoclonal antibody product in dogs with
OA revealed improvement for 1 month,
similar to that expected with NSAIDs, with
no adverse effects (Lascelles et al., 2015).
● Biological therapies (see Chapter 16). Great
attention is currently being given to the use
of various cell‐ or other blood‐derived prep-
arations, generally for intra‐articular injec-
tion, but also being explored for use in
chronic tendinopathies (Canapp et al.,
2016a). The mechanisms of action may be
variable and not completely understood,
but seem to generally involve the activation
of endogenous growth factors and anti‐
inflammatory cytokines, and the suppres-
sion of catabolic and pro‐inflammatory
cytokines. Evidence so far appears to be
generally favorable for each of these prepa-
rations, but studies are still relatively few in
number and limited by widely variable
methodologies of collection, processing,
cost, quality control, invasiveness, applica-
tion, outcome measures, and unknown
highest or wisest utility for a given clinical
condition. Such biological therapies include:❍ Stem cell transplantation: the current
technique involves harvesting of autolo-
gous adipose tissue and isolation of its
mesenchymal stem cells (Vilar et al.,
2014) through various commercial sys-
tems that vary widely in technique and
quality control, then reinjecting the cells
into the same patient’s joint or tendon.
Cells can be banked or cultured for
repeat transplantation. A newer technol-
ogy under investigation uses allogeneic
stem cells from a universal canine donor
population (Harman et al., 2016).
❍ Stromal vascular fraction (SVF): the
non‐cellular portion collected in the pro-
cess of harvesting and isolating autolo-
gous adipose‐derived mesenchymal
stem cells (Upchurch et al., 2016).
❍ Platelet‐rich plasma (PRP): collected
from patients’ blood through any of sev-
eral gravity or centrifugation methods
(Fahie et al., 2013), with widely variable
characteristics, the ideal of which is not
at all known (Franklin et al., 2015). One
recent study also suggests a role in pos-
sible protective effect in partial canine
cruciate injury (Canapp et al., 2016b).