The Growing Importance of Research on CBD for Pets: What Veterinarians Need to Know

By Narda G. Robinson, DO, DVM, MS, FAAMA

A study on nine “purpose-bred” beagles found no significant PK interactions between CBD and phenobarbital, but mild GI issues and hyporexia occurred in some subjects.

Up to a third of dogs and cats receive dietary supplements, many of which contain derivatives of plants. Despite this widespread use, veterinary schools teach nearly nothing about botanical medicine. Consequently, most graduates find themselves ill-equipped to navigate the complexities of plant-based treatments.

The Landscape of Veterinary Supplements

Many veterinary supplements tout “natural” ingredients, yet their quality and transparency vary significantly. Most products lack robust, research-backed information regarding their effectiveness and safety for different species. Unofficial seals of approval from various organizations may boost consumer confidence, but they often lack scientific validation.

Consider the example of Chinese herbal products, which frequently include various plant, mineral, and even animal extracts. Unfortunately, these proprietary blends are often unregulated, leading to uncertainty about their ingredients and potential effects. Without adequate pharmacokinetic data, veterinarians struggle to predict clinical outcomes for their patients.

Cannabidiol (CBD): A Promising Alternative

Fortunately, the cannabis industry has made strides in establishing standards for CBD products. Many reputable suppliers offer certificates of analysis (COA) that validate their quality and purity. Furthermore, some companies have supported rigorous independent research to evaluate the effectiveness of their supplements.

CBD is known for its anxiolytic, anti-inflammatory, immunomodulatory, anticonvulsant, and analgesic properties. Its mechanisms of action involve over 50 molecular targets, but significant gaps remain in our understanding of how CBD interacts with other medications administered concurrently.

Understanding Drug Metabolism: The Role of CYP Enzymes

When substances are ingested, they undergo absorption and processing, primarily in the liver. This process involves cytochrome P450 enzymes (CYPs) that convert xenobiotics into inactive forms, facilitating their elimination from the body. Variations in the levels of these enzymes can significantly impact drug metabolism, meaning that mixing different substances can lead to unexpected interactions.

Currently, the most relevant CYP families concerning CBD metabolism are CYP2C19 and CYP3A4. The former detoxifies approximately 10% of medications, while the latter is responsible for metabolizing the majority of drugs, indicating a high potential for interactions.

CBD Interactions with Common Medications

CYP inducers such as phenobarbital and phenytoin can affect the efficacy of CBD and other medications. In contrast, inhibitors like erythromycin and grapefruit may exacerbate effects. The interplay between CBD and these medications complicates treatment plans for pets, especially those requiring anti-epileptic medications.

Research Insights: Seizure Disorders

A 2021 study highlighted CBD’s interaction with various anti-epileptic drugs (AEDs). The authors noted that the effectiveness of AEDs could change depending on CBD levels in circulation and vice versa. A veterinary assessment of PK interactions between CBD and phenobarbital showed no significant interactions; however, gastrointestinal issues were observed in some subjects.

Musculoskeletal Pain and Mobility Issues

In a prospective, double-blind, placebo-controlled study involving 42 client-owned dogs with mobility issues, noticeable improvements were reported in owner assessments of their pets’ conditions. Such research underscores the necessity for veterinary professionals to stay informed about the therapeutic potentials and limitations of CBD.

Conclusions and Future Directions

The veterinary field is witnessing an increased reliance on CBD and other herbal remedies, but as practitioners, it is crucial to approach these treatments cautiously. Existing gaps in research regarding long-term effects, varying individual responses, and potential interactions must be bridged to better serve our animal patients.

FAQs

What are the benefits of CBD for pets?

CBD has been reported to have various therapeutic effects, including anxiolytic, anti-inflammatory, immunomodulatory, anticonvulsant, and analgesic properties.

Are there any risks associated with using CBD in animals?

Yes, potential risks include gastrointestinal disturbances and interactions with other medications, particularly those metabolized by the liver through cytochrome P450 enzymes.

How can veterinarians safely prescribe CBD?

Veterinarians should review existing research, understand potential drug interactions, and monitor patient responses closely after initiating CBD treatment.

Is there enough research on CBD for pets?

While research on the therapeutic use of CBD for pets is increasing, more studies are needed to fully understand its effects, long-term safety, and any potential interactions with other medications.

The Impact of CBD on Animal Health: Clinical Insights and Considerations

Cannabidiol (CBD) is gaining attention not only in human medicine but also in veterinary practice. As more pet owners turn to CBD for their furry companions, the need to understand its interactions—especially with other medications—becomes crucial. This article explores recent clinical findings regarding CBD’s effects on liver health, particularly in conjunction with non-steroidal anti-inflammatory drugs (NSAIDs), and its implications for managing chronic conditions like cancer.

Understanding CBD and Liver Enzyme Elevation

A recent clinical trial explored the effects of CBD on dogs suffering from various ailments, particularly focusing on those that were also receiving NSAIDs. Notably, serum enzyme levels, specifically alkaline phosphatase (ALP), showed an increase when CBD was co-administered. Alongside this, alanine aminotransferase (ALT) elevations were observed. Such changes in liver values raise critical questions for veterinarians and pet owners alike: Is the addition of CBD directing dogs toward improved quality of life despite these enzyme alterations?

During the study, six pet owners consented to a follow-up of hepatic function through ultrasound and fine needle aspiration. The findings indicated significant changes, including glycogen accumulation and vacuolar hepatopathy. One subject notably presented mild lymphocytic inflammation alongside multifocal necrosis, suggesting potential adverse effects of CBD in sensitive populations.

Analyzing Quality of Life versus Side Effects

The aforementioned study also highlighted side effects associated with CBD administration, predominantly gastrointestinal disturbances such as vomiting and diarrhea. This raises a vital question: does the possible improvement in quality of life offset the risks? For pets dealing with chronic pain or inflammation, the potential benefits of pain relief and enhanced mobility might outweigh the drawbacks of minor side effects. However, it’s critical to assess each case on an individual basis.

Cannabidiol and Cancer Care

In addition to its implications for liver health, CBD’s role in oncology is a growing field of interest. Research indicates that CBD may provide beneficial effects for cancer patients undergoing chemotherapy by alleviating common symptoms such as nausea and anxiety. However, veterinarians must remain vigilant regarding the risks of drug interactions, especially if CBD inhibits the cytochrome P450 enzymes responsible for metabolizing chemotherapeutic agents.

A human study investigating CBD interactions among cancer patients noted potential risks including central nervous system depression and hepatotoxicity. Nevertheless, there is a silver lining; research suggests CBD may enhance the susceptibility of certain cancer types, including breast cancer and glioblastoma, to chemotherapies, potentially improving overall treatment outcomes.

Implications of Herb-Drug Interactions in Veterinary Medicine

Understanding herb-drug interactions is not just a theoretical concern; it has practical implications for veterinary care. The interaction of St. John’s Wort with hormonal contraceptives is a classic example that emphasizes the necessity for veterinary curriculum to cover these topics comprehensively. Given the rising popularity of herbal supplements among pet owners, educating veterinarians on the effects and interactions of these substances is imperative.

Conclusion: A Balanced Perspective on CBD Use

Ultimately, the decision to incorporate CBD into a pet’s treatment plan should be based on a careful evaluation of benefits versus risks. While the potential for enhanced quality of life exists, especially in chronic conditions such as pain and anxiety, vigilant monitoring for side effects and potential drug interactions is essential. As the field of veterinary medicine continues to evolve alongside emerging research on cannabinoids, practitioners must remain informed and make evidence-based decisions for their patients.

References

Finno CJ. Veterinary pet supplements and nutraceuticals. Nutr Today. 2020;55(2):97-101.
Singh A and Zhao K. Chapter Nine – Herb-drug interactions of commonly used Chinese medicinal herbs. International Review of Neurobiology. 2017; 135:197-232.
Balachandran P, Elsohly M, and Hill KP. Cannabidiol interactions with medications, illicit substances, and alcohol: a comprehensive review. J Gen Intern Med. 2021; 36(7):2074-2084.
Castillo-Arellano J, Canseco-Alba A, Cutler SJ, et al. The polypharmacological effects of cannabidiol. Molecules. 2023;28(7):3271.
Doran CE, McGrath S, Bartner LR, et al. Drug-drug interaction between cannabidiol and phenobarbital in healthy dogs. AJVR. 2022; 83(1): 86-94.
Talsma B, Elam LH, McGrath S, Zhou T, Webb CB and Duerr FM (2024) Evaluation of the effect of cannabidiol administration with and without nonsteroidal anti-inflammatory drugs in dogs with mobility disorders: a prospective, double-blind, crossover, placebo-controlled study. Front. Vet. Sci. 11:1449343.
Guedon M, Le Bozec A, Brugel M, et al. Cannabidiol-drug interaction in cancer patients: A retrospective study in a real-life setting. Br J Clin Pharmacol. 2023;89:2322-2328.
Griffiths C, Aikins J, Warshal D, et al. Can cannabidiol affect the efficacy of chemotherapy and epigenetic treatments in cancer? Biomolecules.2021, 11, 766.
Schwarz UI, Buschel B, and Kirch W. Unwanted pregnancy on self-medication with St John’s wort despite hormonal contraception. Br J Clin Pharmacol. 2003; 55:112-113.

What are the common side effects of CBD in pets?

Common side effects in pets include gastrointestinal issues such as vomiting and diarrhea, as well as potential liver enzyme elevations, particularly when co-administered with NSAIDs.

Can CBD interact with cancer treatments in pets?

Yes, CBD can interact with chemotherapy drugs by potentially inhibiting metabolism through certain liver enzymes, which could increase the toxicity of these medications.

Is CBD safe for pets?

While many pets tolerate CBD well, safety depends on dosage, the specific health conditions treated, and potential interactions with other medications. Consulting a veterinarian is recommended before starting CBD.