New Wearable Device For Pain Control?

Hello Summarians!

Pain control is always a hot topic. Whether it’s a new device, an application of older modalities, or confirmation of new protocols, we are always on the lookout for ways to decrease pain in our animal friends.

If you found something interesting in this edition, please share it with a friend!

CBD And Horse Pain

Cannabidiol (CBD) is gaining traction in veterinary medicine, including equine practice, as a potential nutraceutical for pain modulation and behavior management, though regulatory oversight and definitive efficacy studies remain limited. Surveys suggest horse owners and industry professionals are open to CBD use despite a lack of strong clinical evidence. Receptor mapping in equine dorsal root ganglia supports a plausible mechanism of action, as CBD targets TRPV-1, PPAR-γ, GP55, and GP3 receptors involved in pain signaling. 

In this study, oral administration of CBD at 3.48 mg/kg was assessed for antinociceptive effects using thermal and mechanical threshold testing, alongside monitoring of physiological parameters and plasma drug levels. CBD increased thermal pain thresholds compared with placebo and baseline, suggesting activation of C-fiber–mediated pathways linked to thermal nociception, but it had no effect on mechanical thresholds, which primarily involve A-δ fibers. This discrepancy may reflect species differences, differences in acute versus chronic pain models, or limitations of the mechanical threshold model itself. Importantly, post hoc power analysis indicated that detecting a true effect on mechanical threshold would require an unrealistically large sample size. 

Plasma concentrations of CBD achieved levels comparable to those reported in humans, with peak values observed on days 2 and 3, coinciding with increased concentrations of the metabolite CBD-7-COOH. This metabolite accumulated steadily and may have contributed to the antinociceptive effects, though its role in horses remains unexplored. No adverse effects were observed in heart rate, respiratory rate, temperature, gastrointestinal motility, or clinical chemistry, aligning with previous safety studies in equines. 

The findings suggest that CBD at the tested dose is safe and can intermittently elevate thermal pain thresholds in horses, but its effects on mechanical nociception appear negligible in an acute pain setting. Limitations include the short study duration, incomplete dosing in some horses, and reliance on experimental pain models that may not fully capture clinical pain states. Future research should explore higher or more frequent dosing, chronic or neuropathic pain models, and the contribution of CBD metabolites to analgesia in horses. 

Carroll, A. T., Reed, R. A., Berghaus, L. J., McNabney, D., & Knych, H. K. (2025). Oral cannabidiol increases thermal threshold in horses without physiologic adverse effects. American Journal of Veterinary Research https://doi.org/10.2460/ajvr.25.05.0185 

Bottom line — Nice study on acute pain. It would be nice to see chronic pain studies.

Novel Wearable For Pain Control In Dogs

This pilot study explored an outpatient treatment protocol for dogs with suspected pancreatitis, a condition usually managed with inpatient care that provides intravenous fluids, antiemetics, analgesia, and nutrition. Outpatient management poses challenges, particularly regarding the risk of deterioration and provision of adequate analgesia. To address these, the protocol combined supportive care with two innovations: fuzapladib sodium, a leukocyte function–associated antigen-1 inhibitor conditionally approved by the FDA for canine pancreatitis, and a novel wearable subcutaneous continuous rate infusion device delivering hydromorphone for up to 48 hours. These approaches allowed maintenance of analgesia and clinical improvement without hospitalization. 

Most dogs in the study appeared to have mild to moderate pancreatitis, and no cases progressed to severe disease during outpatient management. However, one dog required hospitalization after initial improvement, illustrating the dynamic nature of pancreatitis and the need for close monitoring. The hydromorphone device was well tolerated, and pain scores remained within acceptable limits, though its use was restricted to dogs over 5 kg. Fuzapladib sodium appeared safe, though one possible adverse skin reaction was reported, raising the question of whether it represented an idiosyncratic drug reaction or a systemic disease–related lesion. 

While the protocol reduced costs compared with inpatient care, limitations included the absence of a control group, reliance on suspected rather than confirmed diagnoses, and lack of ultrasound evaluation. These factors limit conclusions about the relative contribution of individual treatments and the true efficacy of the protocol. Nevertheless, the findings suggest that, for carefully selected dogs, outpatient care with standardized supportive treatment, fuzapladib sodium, and innovative opioid delivery may be a safe, lower-cost alternative to hospitalization, provided owners are counseled on the need for re-evaluation if deterioration occurs. 

C. Erger, K. D. Mauro, I. Mendoza-White, M. Brink, S. Heartsill, and H. Cridge, “ Successful Outpatient Pain Management in Dogs With Mild to Moderate Pancreatitis Using a Novel Wearable Device for Continuous Hydromorphone Delivery,” Journal of Veterinary Internal Medicine 39, no. 5 (2025): e70217, https://doi.org/10.1111/jvim.70217. 

Bottom Line — Early results show promise with this protocol.

Comorbidities in Dogs

The study you shared presents one of the largest and most systematic investigations of canine comorbidities to date, leveraging Dog Aging Project (DAP) data from over 26,000 dogs and 160 health conditions. 

It begins by highlighting why dogs are powerful comparative models for human comorbidity research, noting their shared environments, medical care access, and similar aging trajectories. Past research on dog comorbidities has been limited in scope and methods, often failing to account for demographic covariates. This study addresses those gaps by applying logistic regression and the Poisson binomial approach to comorbidity, which better incorporates individual-level risk factors. 

The cohort was balanced by sex and breed background, with a median age of 7.75 years. Most dogs showed multimorbidity, with over 70% having three or more concurrent conditions. Conditions were grouped into 20 body system categories, with skin disorders the most numerous. Fractures, dental disease, and dog bites were among the most common conditions. 

Demographic analyses showed age as the strongest predictor of morbidity, with positive associations across most disease categories, particularly cancer, orthopedic, neurologic, and cardiac. Weight also significantly influenced many conditions, most positively, aligning with known size-related risks. Breed background contributed in condition-specific ways: purebreds were more prone to ear infections, cataracts, and IVDD, while mixed breeds were more affected by cruciate ligament rupture, trauma, and parasitic infections. 

The undirected comorbidity network revealed well-known clusters such as diabetes–cataracts–blindness, Cushing’s disease–alopecia, and strong connections between skin allergies, dermatitis, and ear infections. Additional important associations included hypertension–CKD–proteinuria, anemia. The network fit an exponential rather than scale-free distribution, suggesting morbidities occur independently rather than accumulating proportionally with multimorbidity. 

When stratified by life stage, comorbidity structures shifted with age. Puppies showed no significant patterns, while mature adults had the densest networks, and seniors showed more modularity and central hubs. Certain associations emerged only at specific ages, such as hypertension–CKD in seniors, or cataracts–blindness in mature adults. Interestingly, some unique but less intuitive associations appeared, including conjunctivitis–giardia and cataracts–deafness, hinting at genetic or immunological underpinnings. 

The time-directed analysis, using reported condition onset, clarified progression pathways: diabetes preceded cataracts, dysplasia preceded osteoarthritis, and hypertension preceded CKD. However, some counterintuitive orderings likely reflected reporting lag or diagnostic sequencing rather than true biology. 

The discussion emphasizes that comorbidity in dogs parallels human patterns, reinforcing their value in aging research. It highlights the role of age and body size as fundamental risk factors, while breed background introduces condition-specific risks. The study also demonstrates the potential of comorbidity networks to reveal both expected and novel disease associations, though limitations include recall bias, cross-sectional design, reliance on owner reporting, and demographic skew of the DAP population. 

Ultimately, the work establishes a foundation for longitudinal comorbidity research in dogs, with future integration of genetic, molecular, and veterinary record data expected to refine understanding of disease interconnections, multimorbidity progression, and aging biology. 

Constructing the first comorbidity networks in companion dogs in the Dog Aging Project Antoinette Fang, Lakshin Kumar, Kate E. Creevy, Daniel E.L. Promislow, Jing Ma ,  The Dog Aging Project Consortium Published: August 14, 2025 https://doi.org/10.1371/journal.pcbi.1012728 

Bottom line — Great new information to help us examine population results in dogs.

Just putting things in perspective …