Oral Transmucosal Cannabidiol Oil Formulation as Part of a Multimodal Analgesic Regimen: Effects on Pain Relief and Quality of Life Improvement in Dogs Affected by Spontaneous Osteoarthritis

Pharmacokinetics and tolerability of single-dose enteral cannabidiol and cannabidiolic acid rich hemp in horses (Equus caballus)

The pharmacokinetics and tolerability of cannabinoids and their metabolites were determined in eight horses after enteral administration of a commercial CBD/CBDA-rich hemp oil product. Each horse was administered 2 mg/kg or 8 mg/kg CBD/CBDA or no treatment in a randomized cross-over design. Serial serum samples collected over 48 h were analyzed by high performance liquid chromatography with tandem mass spectrometry. Plasma chemistry analysis was performed at 0 h and 24 h. Vital parameters, pedometry, and blinded mentation and gait evaluations were recorded at intervals up to 24 h. Manure production and gastrointestinal transit time were tracked for 48 h after oil administration. The median maximal concentration of CBD and CBDA were 5.2 and 36.95 ng/mL in the 2 mg/kg group, respectively; and 40.35 and 353.56 ng/mL in the 8 mg/kg group. The median half-life of elimination was not calculated for the 2 mg/kg CBD treatment due to lack of time points above the lower quantifiable limit beyond the Cmax while it was 7.75 h in the 8 mg/kg group. CBDA absorption was biphasic. Pharmacokinetic parameters for tetrahydrocannabinol, tetrahydrocannabinolic acid, cannabigerolic acid, and 7-carboxy cannabidiol are also reported. No significant differences in any of the measured tolerability parameters were demonstrated between treatment groups. Single-dose enteral administration of CBD/CBDA-rich hemp extract up to 8 mg/kg does not appear to produce neurologic, behavioral, or gastrointestinal effects in horses.

Safety study of cannabidiol products in healthy dogs

The tolerability of different cannabinoids given orally to dogs was evaluated in a randomized, non-blinded, negative controlled, parallel design 90-day repeat dose study with a 14-day recovery period. Healthy beagles (16 males and 16 females) were randomized into four treatment groups and treated with either medium chain triglyceride oil as the control or one of the following: broad spectrum cannabidiol, broad spectrum cannabidiol with cannabigerol, or broad spectrum cannabidiol with cannabidiolic acid at 5 mg total cannabinoids/kg body weight/day. Animals were observed daily with detailed clinical examinations conducted weekly. Animals were monitored for an additional 2 weeks after dosing. Body weights, food consumption and clinical pathology evaluations were included in the study. Cannabinoids were well tolerated when healthy male and female beagles were dosed for 90 consecutive days. Annual post-market surveillance data for hemp-derived supplement products sold for use in dogs from 2010 to 2023 (partial year) shows that the rate per 1 million administrations sold is 2.10 for adverse events and 0.01 for serious adverse events. Based on the results of this study, other published studies, and data from extensive post-market surveillance, hemp-derived cannabinoids are well tolerated in healthy dogs at a dose of 5 mg/kg body weight/day.

Case report: Cannabinoid therapy for discoid lupus erythematosus in a dog

Discoid lupus erythematosus (DLE) is a common autoimmune skin disease in dogs. Conventional treatments, such as corticosteroids, can be effective but often have side effects. This case report presents a successful use of cannabinoid therapy (CT) in a dog with DLE resistant to conventional treatment. A 2-year-old mixed-breed dog with a history of DLE presented with worsening lesions despite treatment with corticosteroids and other medications. Liver enzymes levels were elevated, indicating corticosteroid-induced side effects. CT with a CBD-rich full spectrum Cannabis oil was initiated. The dosage was gradually adjusted until the minimum effective dose was found. Within a few weeks of starting CT, the dog showed significant improvement in skin lesions and in liver enzymes levels. After 1 year, the dog remains clinically stable on a low dose of full-spectrum CBD-rich oil. No evidence of DLE recurrence was observed. This case suggests that CT may be a viable alternative or complementary therapy for DLE in dogs, particularly for those experiencing adverse effects from conventional treatments. Further research is warranted to confirm the efficacy and safety of CT for DLE management in dogs.

Improved quality of life and pain relief in mature horses with osteoarthritis after oral transmucosal cannabidiol oil administration as part of an analgesic regimen

The aim of this study was to evaluate the effect of oral cannabidiol (CBD) administration in addition to a conventional analgesic protocol on the clinical signs of 20 horses with mild joint osteoarthritis. The horses were randomly assigned to either the control group (C group) or the cannabidiol group (CBD group). Both groups were treated with phenylbutazone for 5 days. The CBD group received 0.03 mg/kg cannabidiol in hemp oil orally once daily for 14 days in addition to phenylbutazone treatment. All subjects were monitored for clinical parameters, oxidative status and blood counts. Pain and quality of life were also assessed using the Horse Chronic Pain Scale (HCPS). The CBD group showed a significant reduction in heart rate, respiratory rate, white blood cell count and oxidative stress (malondialdehyde lipid peroxidation). A significant reduction in HCPS scores was seen in both groups. Lower scores were recorded in the CBD group (3 med; range: 2/4) than in the C group (7 med; range: 4/10). The addition of a cannabidiol-based product to an analgesic protocol was well tolerated and showed positive effects on the treated subjects, improving their quality of life and pain relief.

Danish dog owners' use and the perceived effect of unlicensed cannabis products in dogs

The interest in the use of medical cannabis has increased in recent years in both human and veterinary fields. In Denmark, there are no veterinary-licensed medical cannabis or cannabinoid supplements, and it is illegal to prescribe or sell cannabinoids intended for the treatment of veterinary patients. This study aimed to explore the unlicensed cannabinoid use in Danish dogs, by questioning dog owners about usage, indication for use, way of purchase, and their perceived effect of the cannabinoid treatment. An anonymous online survey was distributed via social media. The total number of respondents were 2,002, of which 38% indicated using or having administered cannabinoids to their dog. The majority of the respondents confirming the use of cannabinoids (93%) had used cannabidiol drops/oil and only few (4%) reported using Δ9-tetrahydrocannabinol-based products. Most owners (67%) purchased the products online. The three most common indications for use were pain alleviation, behavioural issues, and allergy. When asked about the respondent-perceived effect the majority reported a good or very good effect. The indication with the highest percentage of owner-perceived positive effect (77%) was pain alleviation. This study shows that, despite no licensed veterinary cannabinoid products being available in Denmark, dog owners do supplement their dogs with cannabinoids and the majority of these perceive that the treatment had a positive effect. This supports the need for more evidence-based knowledge in veterinary cannabinoid therapy.

Assessing Dose- and Sex-Dependent Antinociceptive Effects of Cannabidiol and Amitriptyline, Alone and in Combination, and Exploring Mechanism of Action Involving Serotonin 1A Receptors

Inflammatory pain is caused by tissue hypersensitization and is a component of rheumatic diseases, frequently causing chronic pain. Current guidelines use a multimodal approach to pain and sociocultural changes have renewed interest in cannabinoid use, particularly cannabidiol (CBD), for pain. The tricyclic antidepressant amitriptyline (AT) is approved for use in pain-related syndromes, alone and within a multimodal approach. Therefore, we investigated sex- and dose-dependent effects of CBD and AT antinociception in the 2.5% formalin inflammatory pain model. Male and female C57BL/6J mice were pretreated with either vehicle, CBD (0.3-100 mg/kg), or AT (0.1-30 mg/kg) prior to formalin testing. In the acute phase, CBD induced antinociception after administration of 30-100 mg/kg in males and 100 mg/kg in females and in the inflammatory phase at doses of 2.5-100 mg/kg in males and 10-100 mg/kg in females. In the acute phase, AT induced antinociception at 10 mg/kg for all mice, and at 0.3 mg/kg in males and 3 mg/kg in female mice in the inflammatory phase. Combining the calculated median effective doses of CBD and AT produced additive effects for all mice in the acute phase and for males only in the inflammatory phase. Use of selective serotonin 1A receptor antagonist N-[2-[4-(2-methoxyphenyl)-1 piperazinyl]ethyl]-N-2-pyridinylcyclohexanecarboxamide (WAY-100635) maleate (0.1 mg/kg) before co-administration of CBD and AT reversed antinociception in the acute and partially reversed antinociception in the inflammatory phase. Administration of AT was found to enhance cannabinoid receptor type 1mRNA expression only in female mice. These results suggest a role for serotonin and sex in mediating cannabidiol and amitriptyline-induced antinociception in inflammatory pain. SIGNIFICANCE STATEMENT: Inflammatory pain is an important component of both acute and chronic pain. We have found that cannabidiol (CBD) and amitriptyline (AT) show dose-dependent, and that AT additionally shows sex-dependent, antinociceptive effects in an inflammatory pain model. Additionally, the combination of CBD and AT was found to have enhanced antinociceptive effects that is partially reliant of serotonin 1A receptors and supports the use of CBD within a multimodal approach to pain.

Daily dosing of cannabidiol (CBD) demonstrates a positive effect on measures of stress in dogs during repeated exposure to car travel

Dogs are routinely exposed to events that may elicit stress and result in negative emotional states which can impact pet dog welfare. One event many dogs living with people are routinely exposed to is car travel, with many dogs displaying behaviors, along with corresponding physiological responses, that are indicative of stress and anxiety. There are a range of management and treatment options that exist from behavior modification, drug therapy, and supplements, often with varying results. The aim of this study was to evaluate whether multiple doses of a tetrahydrocannabinol-free cannabidiol (CBD) distillate over a period of 6 mo could positively influence measures of stress in dogs. In a blinded, parallel design study, dogs (n = 19) underwent a series of short car journeys (test) where a range of physiological and behavioral measures were collected pre, during, and post-test. The car journeys elicited stress in this population of dogs, as indicated by significant changes (P < 0.05) in several stress-related measures (serum cortisol, heart rate, heart rate variability, whining, lip licking, yawning, and qualitative behavioral ratings) observed from baseline to test, which persisted over repeated car travel events. The mitigating effect of CBD treatment varied by measure, with cortisol, whining, lip licking, and qualitative behavioral ratings indicating a significant (P < 0.05) reduction in canine stress compared to the placebo group for at least one time point. Additional research investigating a range of dog populations and stressors is required to fully understand the complex effect of CBD on canine emotional wellbeing.

Thai veterinarians' perceptions of cannabidiol products for dogs with osteoarthritis: a qualitative interview study

Introduction

The global popularity of cannabidiol (CBD) led to its approval for human use in Thailand and potential use in animals. Many studies revealed CBD's efficacy in treating chronic osteoarthritis (OA) in dogs. To facilitate tailored CBD product development for canine OA and ensure market success, this study explores Thai veterinarians' perception of CBD for canine OA.

Methods

In-depth interviews were conducted with experienced veterinarians who treated OA in ≥25% of their canine patients. Interview questions covered treatment, CBD perception, and adoption. Interviews were held from January to March 2023.

Results

Eleven out of twenty invited veterinarians participated in the study. Though all favored non-steroidal anti-inflammatory drugs (NSAIDs) for OA in dogs, concerns about adverse reactions, including ulcers and renal failure, emerged. CBD was widely known and was perceived positively for pain, inflammation, cancer, and epilepsy. However, half distinguished CBD from marijuana and tetrahydrocannabinol (THC). Ten expressed willingness to prescribe CBD for OA upon robust clinical evidence. Worries centered on product consistency and impurities. Many suggested CBD should be under veterinarians' supervision at first, but this can be relaxing once safety and efficacy are established. CBD products should be chewable tablets, oils, or gelatin capsules with flavors like beef, liver, pork, fish, or seafood.

Conclusion

Though CBD benefits were recognized, knowledge gaps among the participants persisted, warranting robust CBD safety, efficacy, and quality evidence to ensure Thai market success. Comprehensive education, including continuing education for those in practice and incorporating CBD-related topics into the Schools of Veterinary's curriculum, is recommended.

Canine immune cells express high levels of CB1 and CB2 cannabinoid receptors and cannabinoid-mediated alteration of canine cytokine production is vehicle-dependent

With the increased popularity and societal acceptance of marijuana and cannabidiol (CBD) use in humans, there is an interest in using cannabinoids in veterinary medicine. There have been a few placebo-controlled clinical trials in dogs suggesting that cannabis-containing extracts are beneficial for dogs with inflammatory diseases such as osteoarthritis, and there is growing interest in their immunosuppressive potential for the treatment of immune-mediated diseases. Since cannabinoids exhibit anti-inflammatory and immunosuppressive effects in many species, the purpose of these studies was to examine whether the plant-derived cannabinoids, CBD and Δ9-tetrahydrocannabinol (THC), would also suppress immune function in canine peripheral blood mononuclear cells (PBMCs). Another goal was to characterize expression of the cannabinoid receptors, CB1 and CB2, in canine immune cells. We hypothesized that CBD and THC would suppress stimulated cytokine expression and that both cannabinoid receptors would be expressed in canine immune cells. Surprisingly, cannabinoid suppressive effects in canine PMBCs were quite modest, with the most robust effect occurring at early stimulation times and predominantly by THC. We further showed that cannabinoid-mediated suppression was dog- and vehicle-dependent with CBD and THC delivered in dimethyl sulfoxide (DMSO) producing more immune suppressive effects as compared to ethanol (ETOH). PCR, flow cytometry, and immunohistochemical staining demonstrated that both CB1 and CB2 are expressed in canine immune cells. Together these data show that canine immune cells are sensitive to suppression by cannabinoids, but more detailed studies are needed to further understand the mechanisms and broad effects of these compounds in the dog.

Cannabidiol plasma determination and pharmacokinetics conducted at beginning, middle and end of long-term supplementation of a broad-spectrum hemp oil to healthy adult dogs

Introduction

Veterinary hemp products containing cannabidiol (CBD) and negligible psychoactive (THC) have increased popularity since hemp (with <0.3% THC) was removed from schedule 1 substances under the Controlled Substances Act in 2018. This was accompanied by increased CBD research, mostly on the short-term safety and efficacy for inflammatory and neurological conditions. It is imperative to understand how CBD is metabolized or accumulated in the body long-term, thus the goal of the present work was to determine monthly plasma CBD concentrations, as well as changes in pharmacokinetic (PK) parameters in chronically dosed dogs.

Methods

The study was a masked, placebo-controlled, randomized design. Six adult beagles were assigned to placebo, 5 and 10 mg/kg/day CBD treatment groups. Dogs received oral oil treatment once daily for 36 weeks. Blood was collected once every 4 weeks pre- and postprandially for CBD plasma determination (at 0 and 2 h). Pharmacokinetics were conducted at 0, 18 and 36 weeks. Pharmacokinetics and monthly CBD plasma data of dogs who received CBD were analyzed as repeated measures over time using a mixed model, with significance at α = 0.05.

Results

Average plasma CBD at 5 and 10 mg/kg were 97.3 ng/mL and 236.8 ng/mL pre-prandial, 341 ng/mL and 1,068 ng/mL postprandial, respectively. PK parameters suggested CBD accumulation over time, with significant increases in Cmax and AUC at both the 18 and 36-week timepoints. Cmax and AUC were dose proportional. Half-life demonstrated large inter-individual variations and increased (p < 0.05) at weeks 18 and 36 compared to baseline. Volume of distribution was not affected by time or treatment, while MRT increased, and clearance decreased over time (p < 0.05).

Conclusions and clinical importance

Chronic administration of CBD to healthy adult dogs led to a dose-proportional accumulation in the body for 36 weeks, which was confirmed by an increased half-life, total exposure, mean residence time and plasma peak. Our data also suggests that CBD plasma levels may have less daily variation if administered twice daily.

Efficacy and safety of cannabidiol for the treatment of canine osteoarthritis: a systematic review and meta-analysis of animal intervention studies

Introduction

Canine osteoarthritis (OA) is a degenerative disease with chronic inflammation of internal and external joint structures in dogs. Cannabis spp. contains cannabidiol (CBD), a substance known for various potential indications, such as pain relief and anti-inflammatory in various types of animals, including dogs with OA. As CBD is increasingly in the spotlight for medical use, we aimed to perform a systematic review and meta-analysis to evaluate the efficacy and safety of CBD in treating canine OA.

Methods

We searched PubMed, Embase, Scopus, and CAB Direct for animal intervention studies investigating the effects of CBD for canine OA from database inception until February 28, 2023. Study characteristics and findings were summarized. A risk of bias in the included studies was assessed. Meta-analyses were performed using a random-effects model to estimate the effects of CBD on pain scores (0-10), expressed as mean difference (MD) and 95% confidence interval (95% CI). Certainty of evidence was assessed using GRADE.

Results

Five articles were included, which investigated the effects of CBD in 117 dogs with OA. All studies were rated as having a high risk of bias. CBD products varied substantially, i.e., oral full-spectrum CBD oil in four studies, and isolated CBD oil and liposomal CBD oil in another study. Treatment duration varied from 4-12 weeks. Meta-analyses of three studies found that, in dogs with OA, treatment with oral full-spectrum CBD oil may reduce pain severity scores (MD; -0.60, 95% CI; -1.51 to 0.31, I2 = 45.64%, p = 0.19) and pain interference scores (MD; -1.52, 95% CI; -3.84 to 0.80, I2 = 89.59%, p = 0.20) but the certainty of evidence was very low. CBD is generally considered safe and well-tolerated in the short-run, with few mild adverse events observed, such as vomiting and asymptomatic increase in alkaline phosphatase level.

Conclusion

CBD is considered safe for treating canine OA. CBD may reduce pain scores, but the evidence is very uncertain to conclude its clinical efficacy. High-quality clinical trials are needed to further evaluate the roles of CBD in canine OA.

Therapeutic efficacy and pharmacokinetics of liposomal-cannabidiol injection: a pilot clinical study in dogs with naturally-occurring osteoarthritis

Introduction

Osteoarthritis is a common disease in dogs resulting in chronic pain and decreased wellbeing. Common analgesics such as non-steroidal anti-inflammatories may fail to control pain and can produce major adverse effects. Study objectives were to evaluate pharmacokinetics, therapeutic efficacy, and safety of subcutaneous liposomal-cannabidiol (CBD) as an additional analgesic therapy in dogs suffering from naturally-occurring osteoarthritis.

Methods

Six such dogs were recruited following ethics approval and owner consent. Dogs were administered a single subcutaneous injection of 5 mg/kg liposomal-CBD. Plasma concentrations of CBD, blood work, activity monitoring collar data, wellbeing questionnaire (owners) and pain scoring (veterinarian) were performed at baseline and monitored up to six weeks following intervention. Data overtime were compared with baseline using linear-regression mixed-effects. P-value was set at 0.05.

Results

CBD plasma concentrations were observed for 6 weeks; median (range) peak plasma concentration (Cmax) was 45.2 (17.8-72.5) ng/mL, time to Cmax was 4 (2-14) days and half-life was 12.4 (7.7-42.6) days. Median (range) collar activity score was significantly increased on weeks 5-6; from 29 (17-34) to 34 (21-38). Scores of wellbeing and pain evaluations were significantly improved at 2-3 weeks; from 69 (52-78) to 53.5 (41-68), and from 7.5 (6-8) to 5.5 (5-7), respectively. The main adverse effect was minor local swelling for several days in 5/6 dogs.

Conclusion

Liposomal-CBD administered subcutaneously produced detectable CBD plasma concentrations for 6 weeks with minimal side effects and demonstrated reduced pain and increased wellbeing as part of multimodal pain management in dogs suffering from osteoarthritis. Further placebo-controlled studies are of interest.

Pharmacokinetics, efficacy, and safety of cannabidiol in dogs: an update of current knowledge

In the last 5 years, interest has grown in using phytocannabinoids, particularly cannabidiol (CBD), in veterinary medicine to treat several pathologies, including pain, epilepsy, anxiety, nausea, anorexia, skin lesions, and even some types of cancer, among others. Indeed, due to a positive perception of CBD use, many pet owners are increasingly requesting this option to relieve their pets, and many veterinarians are exploring this possibility for their patients. Besides the widespread empiric use of CBD in pets, the research is trying to obtain proof of its efficacy and lack of adverse effects and to know its pharmacokinetics to define an appropriate posology. This review summarizes all data published so far about the canine pharmacokinetics, efficacy, and tolerability of CBD and cannabidiolic acid (CBDA). Despite a certain number of available pharmacokinetic studies, the kinetic profile of CBD has yet to be fully known, probably because of the very different experimental conditions. In terms of efficacy, most studies have tested CBD' ability to relieve osteoarthritic pain. In contrast, few studies have evaluated its role in epilepsy, behavioral disorders, and skin lesions. From obtained results, some evidence exists supporting the beneficial role of CBD. Nevertheless, the limited number of published studies and the occurrence of bias in almost all require caution in interpreting findings. From tolerability studies, CBD' side effects can be classified as mild or unremarkable. However, studies were prevalently focused on short- to medium-term treatment, while CBD is usually employed for long-term treatment. Further studies are warranted to define better whether CBD could be a valid adjunct in canine treatment.

Gabapentin: Clinical Use and Pharmacokinetics in Dogs, Cats, and Horses

Gabapentin is an anticonvulsant drug, which presents an established clinical efficacy in human patients for the management of refractory partial seizures, secondarily generalized tonic-clonic seizures, and for the control of chronic neuropathic pain. Gabapentin was synthesized as a structural analogue of the inhibitory neurotransmitter GABA, with GABA-mimetic effects, able to cross the blood-brain barrier. In veterinary medicine, is extra-label used in combination with other treatments to control seizures when other drugs are no longer effective or become toxic or for neuropathic pain treatment and anxiety. This review aimed to clarify gabapentin use and pharmacokinetic aspects to promote conscious use in dogs, cats, and horses. In dogs, gabapentin was beneficial in the treatment of epilepsy, as well as chronic, neuropathic, and post-operative pain, as well as anxiety. In cats, it showed efficacy in post-ovariohysterectomy-related pain and in anxiety management. In horses, gabapentin has been administered as an analgesic for chronic pain management. In conclusion, when used in combination with other drugs, gabapentin can be considered an interesting therapeutic option for the treatment of neuropathic diseases and analgesia in postoperative and chronic pain. However, despite its beneficial use in different clinical settings, further trials and pharmacokinetic studies are needed for the definition of an effective dosage regimen through proper pharmacokinetic/pharmacodynamic correlation in dogs, cats, and horses.

Cannabidiol for the Treatment of Brain Disorders: Therapeutic Potential and Routes of Administration

The use of cannabidiol (CBD) for treating brain disorders has gained increasing interest. While the mechanism of action of CBD in these conditions is still under investigation, CBD has been shown to affect numerous different drug targets in the brain that are involved in brain disorders. Here we review the preclinical and clinical evidence on the potential therapeutic use of CBD in treating various brain disorders. Moreover, we also examine various drug delivery approaches that have been applied to CBD. Due to the slow absorption and low bioavailability with the current oral CBD therapy, more efficient routes of administration to bypass hepatic metabolism, particularly pulmonary delivery, should be considered. Comparison of pharmacokinetic studies of different delivery routes highlight the advantages of intranasal and inhalation drug delivery over other routes of administration (oral, injection, sublingual, buccal, and transdermal) for treating brain disorders. These two routes of delivery, being non-invasive and able to achieve fast absorption and increase bioavailability, are attracting increasing interest for CBD applications, with more research and development expected in the near future.

The standards of reporting trials in pets (PetSORT): Explanation and elaboration

Well-designed randomized controlled trials (RCTs) provide the best evidence of the primary research designs for evaluating the effectiveness of interventions. However, if RCTs are incompletely reported, the methodological rigor with which they were conducted cannot be reliably evaluated and it may not be possible to replicate the intervention. Missing information also may limit the reader's ability to evaluate the external validity of a trial. Reporting guidelines are available for clinical trials in human healthcare (CONSORT), livestock populations (REFLECT), and preclinical experimental research involving animals (ARRIVE 2.0). The PetSORT guidelines complement these existing guidelines, providing recommendations for reporting controlled trials in pet dogs and cats. The rationale and scientific background are explained for each of the 25 items in the PetSORT reporting recommendations checklist, with examples from well-reported trials.

Scientific Validation of Cannabidiol for Management of Dog and Cat Diseases

Cannabidiol (CBD) is a non-psychotropic phytocannabinoid of the plant Cannabis sativa L. CBD is increasingly being explored as an alternative to conventional therapies to treat health disorders in dogs and cats. Mechanisms of action of CBD have been investigated mostly in rodents and in vitro and include modulation of CB1, CB2, 5-HT, GPR, and opioid receptors. In companion animals, CBD appears to have good bioavailability and safety profile with few side effects at physiological doses. Some dog studies have found CBD to improve clinical signs associated with osteoarthritis, pruritus, and epilepsy. However, further studies are needed to conclude a therapeutic action of CBD for each of these conditions, as well as for decreasing anxiety and aggression in dogs and cats. Herein, we summarize the available scientific evidence associated with the mechanisms of action of CBD, including pharmacokinetics, safety, regulation, and efficacy in ameliorating various health conditions in dogs and cats.

Evaluation of an Oral Supplemental Cannabidiol Product for Acceptability and Performance in Mature Horses

Thirty stock type geldings (15 ± 3 years; 556 ± 63 kg BW) were used in a randomized complete design over 28 days to determine the influence of cannabidiol (CBD) oil supplementation levels on body weight, body condition, and blood chemistry. Horses were randomly assigned to one of three dietary treatments (n = 10 per treatment) formulated with canola oil to provide 1.50 mg CBD/kg BW (TRTA), 0.75 mg CBD/kg BW (TRTB), or 0.00 mg CBD/kg BW (canola oil; CTRL). Treatments were top-dressed onto concentrate and individually administered twice daily. Horses were maintained in adjacent dry lots and received coastal bermudagrass hay ad libitum. Body weight and body condition scores (BCS) were obtained every 14 days. On day 0 and 28, blood was collected via jugular venipuncture and serum was harvested to perform a blood chemistry panel and drugs of abuse screening at the Texas Veterinary Medical Diagnostic Laboratory. Data were analyzed using PROC MIXED of SAS (v9.4), and the model included treatment, time, and the treatment × time interaction, and linear and quadratic orthogonal polynomial contrasts to partition sum of squares. Analysis of composited treatment samples revealed lower CBD concentrations than indicated from initial testing by the manufacturer (0.13 mg CBD/kg in TRTA; 0.12 mg CBD/kg in TRTB). At this level of supplementation, canola-based CBD oil was well-accepted by mature horses, banned substances were not detectable in blood, and blood chemistry parameters were not adversely affected as a result of supplementation. More research is warranted to describe the discrepancy between formulated levels compared to tested levels of CBD in the canola-based supplement.

Pharmacokinetics of cannabidiol following single oral and oral transmucosal administration in dogs

Introduction

In the last few years, different formulations containing cannabidiol (CBD) were tested with regard to its efficacy on chronic pain, refractory epilepsy, anxiety, aggressive behavior and atopic dermatitis in dogs. CBD is generally administered orally, but its low bioavailability, probably due to a first-pass metabolism, represents a great limitation. The aim of this study was to evaluate if CBD bioavailability increases after oral transmucosal administration (OTM) compared to oral treatment.

Methods

Twelve dogs diagnosed with mild chronic pain were enrolled in the study and treated once orally or OTM (6 dogs/group) with a pure CBD in oil formulation at a dosing rate of 1 mg/kg b.w. At prefixed time points, blood samples were collected to define CBD plasma concentrations vs. time profiles, and the main pharmacokinetics parameters were obtained by non-compartmental model.

Results

CBD Cmax, Tmax, terminal half-life and AUC_{0 - t} were 206.77 ± 167 and 200.33 ± 158.33 ng/mL, 2.17 ± 0.98 and 1.92 ± 1.11 h, 2.67 ± 0.53 and 2.62 ± 0.64 h, 647.51 ± 453.17, and 536.05 ± 370.21 h^*ng/mL, following oral and OTM administration, respectively. No significant difference in pharmacokinetic parameters were observed between treatments.

Discussion

The OTM administration did not increase cannabidiol bioavailability compared to oral treatment. The almost perfectly superimposable mean plasma concentrations of cannabidiol following the two treatments suggests that CBD is not able to be adsorbed by the oral mucosa or that its absorption is very scarce, and that CBD is swallowed and absorbed in the gastrointestinal tract.

Evaluation of the efficacy of a cannabidiol and cannabidiolic acid rich hemp extract for pain in dogs following a tibial plateau leveling osteotomy

Objective

To determine the impact of a cannabidiol (CBD) and cannabidiolic acid (CBDA) rich hemp product on acute post-operative pain in dogs following a tibial plateau leveling osteotomy (TPLO), and to evaluate for changes in early bone healing, serum chemistry profiles, and complete blood counts.

Methods

In this randomized, placebo controlled, blinded clinical trial, 44 client-owned dogs were assigned to receive either a CBD/CBDA product dosed at 2-2.5 mg/kg PO every 12 h or a placebo for 4 weeks following a TPLO. Variables evaluated before (week 0), and at 2 and 4 weeks post-operatively included standardized veterinary assessments for pain score, weight-bearing, and lameness, the Canine Brief Pain Inventory (pain interference score-PIS, pain severity score-PSS), and serum biochemistry. Complete blood counts were performed at weeks 0 and 4. Additionally, orthogonal radiographs evaluating the degree of healing were taken at week 4. A mixed model analysis, analyzing changes of variables of interest from enrollment baseline to all other time points was utilized, with a p-value ≤ 0.05 considered significant.

Results

Of the 44 enrolled patients, 3 were lost to follow up and excluded from analysis. No significant differences were noted between placebo (n = 19) and CBD/CBDA (n = 22) groups at any point in pain score, degree of lameness, degree of weight-bearing, PIS, PSS, or radiographic healing of the osteotomy. A significant finding of elevation of ALP above normal reference range in the treatment group was identified (p = 0.02) and eosinophil count was affected by treatment (p = 0.01), increasing from baseline in placebo and decreasing in treatment groups. Finally, a significant difference (p = 0.03) was noted at 2 weeks post-operatively where 4 patients in the placebo group and no treatment patients received trazodone to facilitate activity restrictions.

Clinical significance

Use of a CBD/CBDA rich hemp product dosed at 2-2.5 mg/kg PO every 12 h did not have a significant impact on pain or delay early bone healing. A statistically significant increase in ALP, decrease in eosinophils, and reduced use of trazodone was identified in the treatment group.

The role of cannabinoids in pain modulation in companion animals

The use of cannabinoids in both veterinary and human medicine is controversial for legal and ethical reasons. Nonetheless, the availability and therapeutic use of naturally occurring or synthetic phytocannabinoids, such as Δ⁹-tetrahydrocannabidiol and cannabidiol, have been the focus of attention in studies regarding their medical uses. This review aims to examine the role of cannabinoids in pain modulation by analyzing scientific findings regarding the signaling pathways of the endocannabinoid system and discussing the analgesic effects of synthetic cannabinoids compared to cannabinoid extracts and the extent and involvement of their receptors. In animals, studies have shown the analgesic properties of these substances and the role of the cannabinoid binding -1 (CB1) and cannabinoid binding -2 (CB2) receptors in the endocannabinoid system to modulate acute, chronic and neuropathic pain. This system consists of three main components: endogenous ligands (anandamide and 2-arachidonoylglycerol), G protein-coupled receptors and enzymes that degrade and recycle the ligands. Evidence suggests that their interaction with CB1 receptors inhibits signaling in pain pathways and causes psychoactive effects. On the other hand, CB2 receptors are associated with anti-inflammatory and analgesic reactions and effects on the immune system. Cannabis extracts and their synthetic derivatives are an effective therapeutic tool that contributes to compassionate pain care and participates in its multimodal management. However, the endocannabinoid system interacts with different endogenous ligands and neurotransmitters, thus offering other therapeutic possibilities in dogs and cats, such is the case of those patients who suffer from seizures or epilepsy, contact and atopic dermatitis, degenerative myelopathies, asthma, diabetes and glaucoma, among other inflammatory diseases. Moreover, these compounds have been shown to possess antineoplastic, appetite-stimulating, and antiemetic properties. Ultimately, the study of the endocannabinoid system, its ligands, receptors, mechanism of action, and signaling, has contributed to the development of research that shows that hemp-derived and their synthetic derivatives are an effective therapeutic alternative in the multimodal management of pain in dogs and cats due to their ability to prevent peripheral and central sensitization.

Pharmacokinetics of escalating single-dose administration of cannabidiol to cats

This study aimed to assess the single-dose pharmacokinetics and tolerability of a cannabidiol (CBD) isolate in sunflower oil with escalating oral doses in eight healthy, purpose-bred cats. Eight cats were randomized into six dosing groups of four cats each. Cats were administered a single 2.5, 5, 10, 20, 40, or 80 mg/kg dose orally with at least a two-week washout in between doses. Behavior scoring, complete blood count, serum biochemistry analysis, physical examination, and CBD plasma levels were evaluated before and after dosing. All cats successfully completed the study. CBD was measured in the plasma of all cats dosed with CBD oil. The Cmax and AUC increased in a dose-proportional fashion across all dosing groups. There were no major bloodwork or behavioral changes although the BUN and creatinine values decreased after treatment across all doses. No adverse effects were observed, and behavioral changes were limited to head shaking, lip smacking, and hypersalivation immediately following dose administration. Single orally administered CBD doses up to 80 mg/kg were safe and well tolerated in this cohort of cats and display dose-proportional pharmacokinetics across a broad concentration.

Safety and Efficacy of the Therapeutic Use of Cannabis-Based Products in the Treatment of Dogs: An Integrative Review

The use of cannabis-based products for therapeutic purposes is a reality in the field of animal health. However, although cannabis is considered safe when appropriately used by human patients, cannabis-based products can pose a risk to companion animals such as dogs, depending on their composition or route of administration. Thus, this article discusses aspects of the safety and efficacy of different cannabis-based products in dogs' treatment through an integrative review. The review was systematically performed in Medline (via Pubmed^®) and Latin American and Caribbean Health Sciences Literature (LILACS) databases, with period restriction (between 1990 and 2021). The qualified articles (n=19), which met the previously established inclusion criteria, were critically evaluated. Based on the literature review, it is possible to infer safety in the administration of cannabis-based products for the treatment of dogs, especially products rich in cannabidiol (CBD), free or with low concentrations of tetrahydrocannabinol, under the conditions evaluated. In addition, CBD products potentially promote improved quality of life and reduce pain perception in animals affected by canine osteoarthritis. Finally, owing to the lack of large-scale and robust clinical research studies, the performance of clinical trials, considering the individual characteristics of each cannabis-based product (composition, concentration, nature of adjuvants, dosage form, route of administration), is strongly encouraged.

Advances in the pharmaceutical treatment options for canine osteoarthritis

Canine osteoarthritis is a significant cause of pain in many dogs and can therefore compromise animal welfare. As the understanding of the biology and pain mechanisms underpinning osteoarthritis grows, so do the number of treatments available to manage it. Over the last decade, there have been a number of advances in the pharmaceutical treatment options available for dogs with osteoarthritis, as well as an increasing number of clinical trials investigating the efficacy of pre-existing treatments. This review aims to examine the current evidence behind pharmaceutical treatment options for canine osteoarthritis, including non-steroidal anti-inflammatory drugs, piprants, monoclonal antibodies, adjunctive analgesics, structure modifying osteoarthritis drugs and regenerative therapies.

A 2022 Systematic Review and Meta-Analysis of Enriched Therapeutic Diets and Nutraceuticals in Canine and Feline Osteoarthritis

With osteoarthritis being the most common degenerative disease in pet animals, a very broad panel of natural health products is available on the market for its management. The aim of this systematic review and meta-analysis, registered on PROSPERO (CRD42021279368), was to test for the evidence of clinical analgesia efficacy of fortified foods and nutraceuticals administered in dogs and cats affected by osteoarthritis. In four electronic bibliographic databases, 1578 publications were retrieved plus 20 additional publications from internal sources. Fifty-seven articles were included, comprising 72 trials divided into nine different categories of natural health compound. The efficacy assessment, associated to the level of quality of each trial, presented an evident clinical analgesic efficacy for omega-3-enriched diets, omega-3 supplements and cannabidiol (to a lesser degree). Our analyses showed a weak efficacy of collagen and a very marked non-effect of chondroitin-glucosamine nutraceuticals, which leads us to recommend that the latter products should no longer be recommended for pain management in canine and feline osteoarthritis.

Effects of a supplement containing Cannabidiol (CBD) on sedation and ataxia scores and health: Effects of Cannabidiol on Sedation and Ataxia

Supplements containing Cannabidiol (CBD) are available for horses, however, few studies have been published on their effects on behavior and health parameters. The purpose of this study was to determine if a daily oral supplement containing CBD would cause sedation, ataxia or alterations in other health parameters during administration for 56 days. Twenty clinically healthy adult Thoroughbred horses were housed in stalls. Before treatment was initiated, a complete physical examination, complete blood count (CBC) and biochemical panel were evaluated. In addition, horses were examined for sedation and ataxia using standard scoring systems. Horses were randomly divided into two treatment groups, treated (supplement pellets containing CBD as Hemp Extract, 150 mg) or control (supplement pellets without CBD). Horses were treated daily and sedation and ataxia scores were assigned by two masked observers once weekly for 56 days. Horses were monitored daily for clinical signs or adverse events and body weights were recorded weekly. A CBC and biochemical panel were repeated on days 28 and 56, two hours after administration of the supplement. The supplement was readily consumed by the horses and no adverse effects were seen over the treatment period. Sedation and ataxia scores ranged from 0 to 2 for all horses during the weekly examinations and there was no statistical difference between treatment groups. There were no treatment effects on blood values, including indicators of anemia and blood proteins, liver enzymes, kidney values, electrolytes or calcium. Body weight significantly increased in all horses, by Day 56 compared to Day 0 but no treatment by day effect was noted. The CBD supplement (150 mg) was readily consumed and safe and did not result in changes in mentation, gait, or other health parameters, and no adverse clinical signs were observed during 56 days of oral administration.

Serum Cannabinoid 24 h and 1 Week Steady State Pharmacokinetic Assessment in Cats Using a CBD/CBDA Rich Hemp Paste

Hemp based cannabinoids have gained popularity in veterinary medicine due to the potential to treat pain, seizure disorders and dermatological maladies in dogs. Cat owners are also using hemp-based products for arthritis, anxiety and neoplastic disorders with no studies assessing hemp cannabinoids, namely cannabidiol efficacy, for such disorders. Initial twenty-four pharmacokinetic and chronic dosing serum concentration in cats are sparse. The aim of our study was to assess 8 cats physiological and 24 h and 1-week steady state pharmacokinetic response to a cannabidiol (CBD) and cannabidiolic acid (CBDA) rich hemp in a palatable oral paste. Using a standard dose of paste (6.4 mg/CBD + CBDA 5.3 mg/gram) across 8 cats weighing between 4.2 and 5.4 kg showed an average maximal concentration of CBD at 282.0 ± 149.4 ng/mL with a half-life of ~2.1 ± 1.1 h, and CBDA concentrations of 1,011.3 ± 495.4 ng/mL with a half-life of ~2.7 ± 1.4 h, showing superior absorption of CBDA. After twice daily dosing for 1 week the serum concentrations 6 h after a morning dosing showed that the acidic forms of the cannabinoids were approximately double the concentration of the non-acidic forms like CBD and Δ9- tetrahydrocannabinol (THC). The results of this study compared to two other recent studies suggest that the absorption in this specific paste product may be superior to oil bases used previously, and show that the acidic forms of cannabinoids appear to be absorbed better than the non-acidic forms. More importantly, physical and behavioral examinations every morning after dosing showed no adverse events related to neurological function or behavioral alterations. In addition, bloodwork after 1 week of treatment showed no clinically significant serum biochemical alterations as a reflection of hepatic and renal function all remaining within the reference ranges set by the diagnostic laboratory suggesting that short-term treatment was safe.

Use of cannabis in the treatment of animals: a systematic review of randomized clinical trials

Cannabis is used in the treatment of several human conditions; however, its use is still less explored in veterinary medicine. This systematic review aims to summarize the evidence of efficacy and safety of the use of cannabis for the treatment of animal disease. A literature search was performed for studies published until 16 March 2021 in five databases. Randomized clinical trials (RCTs) that reported the efficacy or safety of cannabis in the treatment of animal disease were included. The RoB 2 Tool was used to assess the risk of bias. A total of 2427 records were identified, of which six studies fully met the eligibility criteria. RCTs were conducted in dogs with osteoarthritis (n = 4), with epilepsy (n = 1), and with behavioral disorders (n = 1). All studies used cannabidiol (CBD) oil in monotherapy or in combination with other drugs. Studies used CBD at 2 or 2.5 mg kg^-1 twice daily (n = 4), orally (n = 5), during 4 or 6 weeks (n = 3), and compared CBD with placebo (n = 5). CBD significantly reduced pain and increased activity in dogs with osteoarthritis (n = 3). Moreover, CBD significantly reduced the frequency of seizures in dogs with epilepsy (n = 1) and the aggressive behavior of dogs (n = 1). Although promising results were identified, studies were heterogeneous and presented risks of bias that required caution in the interpretation of findings. Therefore, there was some evidence to support the use of CBD in dogs with osteoarthritis to reduce pain and increased activity, but limited evidence against epilepsy and behavioral problems. In addition, CBD was well tolerated with mild adverse effects. More RCTs with high quality of evidence are needed, including greater numbers of animal subjects, additional species, and clear readout measures to confirm these findings.

Cannabidiol (CBD) in Rheumatic Diseases (Musculoskeletal Pain)

Purpose of Review

This review will address the many uncertainties surrounding the medical use of cannabidiol (CBD). We will begin with an overview of the legal and commercial environment, examine recent preclinical and clinical evidence on CBD, explore questions concerning CBD raised by healthcare professionals and patients, investigate dosing regimens and methods of administration, and address current challenges in the accumulation of sound evidence.

Recent Findings

CBD has potential for relief of symptoms of pain, sleep, and mood disturbance in rheumatology patients, but sound clinical evidence is lacking. CBD is safe when accessed from a regulated source, whereas wellness products are less reliable regarding content and contaminants. Dosing for symptom relief has not yet been established.

Summary

As many rheumatology patients are trying CBD as a self-management strategy, the healthcare community must urgently accrue sound evidence for effect.

A Case Report of Subcutaneously Injected Liposomal Cannabidiol Formulation Used as a Compassion Therapy for Pain Management in a Dog

A 14-year-old intact mixed breed dog (26 kg) was submitted for a novel cannabidiol (CBD) analgesic treatment. The dog was cachectic and had a testicular neoplasia, hip and elbow osteoarthritis and severe cervical pain. Analgesic treatment included canine osteoarthritic supplement, robencoxib and gabapentin. An additional liposomal CBD injectable formulation at 5 mg/kg was administered subcutaneously between the shoulder blades. The dog was monitored using an activity monitoring collar (PetPace), owner wellbeing questionnaire (Canine Brief Pain Inventory; CBPI), pain interactive visual analog scale (iVAS), blood work and CBD plasma concentrations. A week from the injection and up to 3 weeks afterwards the dog had improved CBPI and iVAS pain scores, and increased collar activity scores. CBD was quantified in plasma for 28 days. Due to disease progression, further difficulty to rise and walk, and relapse to pain after 3 weeks, the owners requested a second liposomal CBD injection, which was performed 4 weeks following the first injection using 3 mg/kg dose. Two days later, the dog was found dead in the yard under direct sun, while environmental temperature was 37°C. Major findings on necropsy revealed evidence of heat stroke and severe cervical disc protrusion with spinal hematoma, none related to liposomal CBD. In conclusion, subcutaneous liposomal CBD produced quantifiable CBD plasma concentrations for 28 days and may be an effective additional treatment as part of multimodal pain management in dogs.

Proposed Canadian Consensus Guidelines on Osteoarthritis Treatment Based on OA-COAST Stages 1–4

The Canadian consensus guidelines on OA treatment were created from a diverse group of experts, with a strong clinical and/or academic background in treating OA in dogs. The document is a summary of the treatment recommendations made by the group, with treatments being divided into either a core or secondary recommendation. Each treatment or modality is then summarized in the context of available research based support and clinical experience, as the treatment of OA continues to be a multimodal and commonly a multidisciplinary as well as individualized approach. The guidelines aim to help clinicians by providing clear and clinically relevant information about treatment options based on COAST defined OA stages 1–4.

Feeding treats containing cannabidiol (CBD) did not alter canine immune response to immunization with a novel antigen

Due to the potential risk for cannabidiol (CBD) to negatively impact the immune system, the objective of the current study was to evaluate the effect of CBD on the canine immune response to immunization with a novel antigen, keyhole limpet hemocyanin (KLH). Thirty-two dogs (22.4 ± 6.3 kg BW) were utilized in a completely randomized design with treatments consisting of 5 mg CBD/kg BW/d and a control administered orally via treats. After a 7-d acclimation to treatments, dogs were immunized with 10 mg/dog of KLH via intramuscular injection into the semimembranosus muscle region, which was repeated in 14 d. Blood samples were collected at baseline and weekly for 28 d after initial KLH immunization for analysis of hematology, serum chemistry, and immunoglobulins. Data were analyzed using the MIXED procedure in SAS including the fixed effects of treatment, day, and the treatment by day interaction. Both primary and secondary KLH immunization produced robust immune responses. Most hematological and serum chemistry variables remained within normal reference ranges for dogs across both treatments throughout the study. Alkaline phosphatase, while within normal reference range and similar between treatments at baseline and on d 7 (P = 0.994 and 0.183, respectively), was elevated for CBD-treated dogs versus control on d 14, 21, and 28 (P = 0.006, 0.027, and 0.014, respectively). Both total and KLH-specific IgG and IgM were similar between treatments throughout the study (P > 0.05), although total IgM peaked earlier in control dogs compared to those receiving CBD. Despite the minor shift in the timing of the total IgM peak, CBD did not appear to exhibit humoral immunosuppressive effects when supplemented at 5 mg/kg BW/d. However, this work does highlight the potential for CBD to alter liver function and the need for further safety evaluations of CBD use in dogs utilizing longer-term studies and multiple CBD doses.

Alteration of the Canine Metabolome After a 3-Week Supplementation of Cannabidiol (CBD) Containing Treats: An Exploratory Study of Healthy Animals

Despite the increased interest and widespread use of cannabidiol (CBD) in humans and companion animals, much remains to be learned about its effects on health and physiology. Metabolomics is a useful tool to evaluate changes in the health status of animals and to analyze metabolic alterations caused by diet, disease, or other factors. Thus, the purpose of this investigation was to evaluate the impact of CBD supplementation on the canine plasma metabolome. Sixteen dogs (18.2 ± 3.4 kg BW) were utilized in a completely randomized design with treatments consisting of control and 4.5 mg CBD/kg BW/d. After 21 d of treatment, blood was collected ~2 h after treat consumption. Plasma collected from samples was analyzed using CIL/LC-MS-based untargeted metabolomics to analyze amine/phenol- and carbonyl-containing metabolites. Metabolites that differed - fold change (FC) ≥ 1.2 or ≤ 0.83 and false discovery ratio (FDR) ≤ 0.05 - between the two treatments were identified using a volcano plot. Biomarker analysis based on receiver operating characteristic (ROC) curves was performed to identify biomarker candidates (area under ROC ≥ 0.90) of the effects of CBD supplementation. Volcano plot analysis revealed that 32 amine/phenol-containing metabolites and five carbonyl-containing metabolites were differentially altered (FC ≥ 1.2 or ≤ 0.83, FDR ≤ 0.05) by CBD; these metabolites are involved in the metabolism of amino acids, glucose, vitamins, nucleotides, and hydroxycinnamic acid derivatives. Biomarker analysis identified 24 amine/phenol-containing metabolites and 1 carbonyl-containing metabolite as candidate biomarkers of the effects of CBD (area under ROC ≥ 0.90; P < 0.01). Results of this study indicate that 3 weeks of 4.5 mg CBD/kg BW/d supplementation altered the canine metabolome. Additional work is warranted to investigate the physiological relevance of these changes.

Feeding Cannabidiol (CBD)-Containing Treats Did Not Affect Canine Daily Voluntary Activity

Growing public interest in the use of cannabidiol (CBD) for companion animals has amplified the need to elucidate potential impacts. The purpose of this investigation was to determine the influence of CBD on the daily activity of adult dogs. Twenty-four dogs (18.0 ± 3.4 kg, 9 months-4 years old) of various mixed breeds were utilized in a randomized complete block design with treatments targeted at 0 and 2.5 mg (LOW) and at 5.0 mg (HIGH) CBD/kg body weight (BW) per day split between two treats administered after twice-daily exercise (0700-0900 and 1,700-1,900 h). Four hours each day [1,000-1,200 h (a.m.) and 1,330-1,530 h (p.m.)] were designated as times when no people entered the kennels, with 2 h designated as Quiet time and the other 2 h as Music time, when calming music played over speakers. Quiet and Music sessions were randomly allotted to daily a.m. or p.m. times. Activity monitors were fitted to dogs' collars for continuous collection of activity data. Data were collected over a 14-day baseline period to establish the activity patterns and block dogs by activity level (high or low) before randomly assigning dogs within each block to treatments. After 7 days of treatment acclimation, activity data were collected for 14 days. Data were examined for differences using the MIXED procedure in SAS including effects of treatment, day, session (Quiet or Music), time of day (a.m. or p.m.), and accompanying interactions. CBD (LOW and HIGH) did not alter the total daily activity points (P = 0.985) or activity duration (P = 0.882). CBD tended (P = 0.071) to reduce total daily scratching compared with the control. Dogs were more active in p.m. sessions than in a.m. sessions (P < 0.001). During the p.m. session, dogs receiving HIGH tended (P = 0.091) to be less active than the control (CON). During the a.m. and p.m. sessions, CBD reduced scratching compared with CON (P = 0.030). CBD did not affect the activity duration during exercise periods (P = 0.143). These results indicate that, when supplemented with up to 4.5 mg CBD/kg BW/day, CBD does not impact the daily activity of adult dogs, but may exert an antipruritic effect.

Pain Management in Small Ruminants and Camelids: Applications and Strategies

Small ruminants are increasing in popularity as production and companion animals in the United States, and among sheep, goats, and camelids there are many disease processes and management techniques that have the potential to result in painful or noxious stimuli. In these species, many medications and therapeutic techniques can be used to reduce or eliminate the long-term consequences of pain. In this second portion of the review, we focus on the application of pain management in these species. These strategies include mono- and multimodal and the use of precision pain management, such as epidural drug administration, regional perfusions, and transdermal applications.

Oral Transmucosal or Intramuscular Administration of Dexmedetomidine-Methadone Combination in Dogs: Sedative and Physiological Effects

Simple Summary

During the last decade, new alternative non-invasive administration routes for drug delivery have gained interest in veterinary medicine. The administration of drugs via the oral transmucosal route is non-invasive, painless, easy to perform, and generally well tolerated. Furthermore, it avoids gastric acid degradation typical of oral administration. All these characteristics contribute to make this administration route very attractive, especially for veterinary patients who are difficult to inject, fearful, or anxious. In contrast, intramuscular injection is associated with pain and requires more invasive restraint, potentially incrementing patients’ discomfort. The aim of this study was to assess and compare the sedative and clinical effects of a dexmedetomidine–methadone combination following either oral transmucosal and intramuscular administration in healthy dogs and to record any possible adverse effects following each administration route. The present study suggests that oral transmucosal administration of dexmedetomidine and methadone combination provided a satisfactory level of sedation, allowing safe handling of the patients with less pronounced cardiorespiratory effects. Indeed, thanks to the lesser impact on the cardiac function, it could be considered as a useful option for those patients difficult to restrain in which cardiovascular stability should be preserved.

Abstract

The aim of this study was to compare the sedative and physiological effects following either oral transmucosal (OTM) or intramuscular administration of dexmedetomidine–methadone combination in healthy dogs. Thirty dogs were randomly assigned to receive a dexmedetomidine–methadone combination either by the OTM (n = 15) or intramuscular (n = 15) route. Sedation was scored 10, 20, and 30 min after drugs administration. Heart rate (HR), non-invasive blood pressure (NIBP), respiratory rate (f_R), and body rectal temperature were recorded before drugs administration and then every 10 min for 30 min. Propofol dose required for orotracheal intubation was recorded. Sedation scores increased over time within both groups with higher values in intramuscular group (p < 0.05). Within each group, HR decreased significantly compared with baseline (p < 0.001) and was significantly lower in intramuscular group compared with the OTM group (p < 0.001). In both groups, NIBP increased significantly compared with baseline (p < 0.05). In the intramuscular group, f_R was lower compared with the OTM group at all the observational time points (p < 0.001). Propofol dose was lower in the intramuscular group (p < 0.05). Compared to intramuscular dexmedetomidine–methadone, OTM combination produced lower but effective sedation in healthy dogs.