The 2023 World Small Animal Veterinary Association (WSAVA)

The second version of the list of essential medicines is presented by members of the WSAVA Therapeutic Guidelines Group (TGG) following extensive internal and external peer-review. Internal peer-review was provided by TGG members in 2023, whereas external peer-review was performed by board-certified individuals and other WSAVA working groups. Additionally, there was a 3-month audit (January to March 2023) allowing any individual including WSAVA member affiliates to provide comments, suggestions and overall feedback. Any comment received was carefully considered by the TGG taking into consideration the definitions of core and complementary medicine. The updated (version 2) list is a product of several rounds of revision and based on expert consensus.

This list of essential medicines should allow veterinarians to provide proper preventive care and treatment of the most frequent and important diseases in dogs and cats while maintaining appropriate animal welfare standards. The purpose of the list is to improve and facilitate regulatory oversight for ensuring appropriate medicines availability, drug quality, use and pharmacovigilance, while mitigating the growing black/counterfeit market of pharmaceutical products. The list of essential medicines is not intended to define what medicines should be always available within the clinic/hospital nor a drug compendium; rather that veterinarians should have ready access to these (medicines) if required for the prevention and treatment of specific diseases and conditions. Additionally, the committee understands that there is no “one-size fits all” and that there may be specific medicines used for endemic/epidemic diseases in some countries that the list does not cover. For example, the essential antimicrobials were defined as those medicines that are recommended as first line agents for treatment of at least one common disease condition but also taking into consideration the issue of antimicrobial resistance.

Essential medicines are those that satisfy the primary health care and welfare needs of cats and dogs.

The definitions of essential medicines are based on a similar list of essential medicines in human medicine by the World Health Organization (https://www.who.int/medicines/publications/essentialmedicines/en/). However, our current approach does not involve, e.g. extensive systematic reviews and meta-analysis to demonstrate evidence-based information for each medicine as this may not be always achievable in veterinary medicine. Medicines presented in the list may or may not be approved and/or licensed for use in veterinary medicine, which may vary from country to country. From a regulatory standpoint, the list should be adapted in accordance with specific regional or national needs and conditions. The presence of a medicine in the essential medicines list carries no assurance as to the pharmaceutical quality of products containing that medicine. It is the responsibility of the relevant national or regional drug regulatory authority to ensure that each product is of appropriate pharmaceutical quality (including stability) and that, when relevant, bioequivalent products can be interchangeable. Individuals should be also aware of potential different concentrations and formulations of each compound/medicine, and possible drug combinations present in a commercial product. Additionally, this list is not meant to be used as a reference for dosage regimens, drug interactions, indications or contra-indications, adverse effects or description of pharmacologic effects. It does not describe what medicines require monitoring, specific means of disposal/elimination/record keeping or follow-up consultations as the list should not be used as guidance for therapy.

Essential medicines are presented in alphabetical order and divided by either drug category (anaesthetic, analgesics, immunomodulators, oncology drugs, sedatives, vaccines, antiparasitics and antimicrobials, including antibacterial, antifungal, antiprotozoal and antiviral drugs) or organ system/specialty (cardiorespiratory and renal, endocrinology, gastrointestinal, neurology, ophthalmology or reproduction). The essential list of medicines for dermatology is presented in other sections of the document (e.g. immunomodulators, antimicrobials, antiparasitics, etc.). Cross-reference between a drug category and an organ system is acknowledged where appropriate. Some veterinary specialties may not be listed as their lists of essential medicines have been merged into another drug category or organ system.

Essential medicines are selected with due regard to disease prevalence and public/animal health relevance, evidence of clinical efficacy and safety, and comparative costs and cost-effectiveness. These medicines can be rarely replaced by other medicines and their absence could compromise public/animal health and welfare.

The core list presents a list of minimum medicine needs for a basic health care system, listing the most efficacious, safe and cost-effective medicines for priority conditions. Priority conditions are selected based on current and estimated future public/animal health relevance, and potential for safe and cost-effective treatment.

The complementary list presents essential medicines for priority diseases, for which advanced diagnostic or monitoring facilities, and/or advanced medical care, and/or advanced training are needed. In case of doubt, medicines may also be listed as complementary based on consistently higher cost or less attractive cost-effectiveness in a variety of settings and wide availability in the profession.

(The WSAVA Global Pain Council has published the 2022 WSAVA guidelines for appropriate recognition, assessment and treatment of pain including protocols with different drug availability – https://onlinelibrary.wiley.com/doi/10.1111/jsap.13566. The WSAVA Global Pain Council has published information on the minimum analgesic availability – https://www.wsava.org/WSAVA/media/Documents/Committee%20Resources/WSAVA-GPC-Position-minimum-analgesic-availability.pdf.)

(The relapsed disease using rescue protocols or cases of toxicity with a specific drug cannot always be treated with this essential list of drugs).

Paulo V. Steagall: Conceptualization (equal); investigation (equal); methodology (equal); project administration (equal); supervision (equal); writing – original draft (equal); writing – review and editing (equal). Jennifer L. Granick: Investigation (equal); validation (equal); writing – review and editing (equal). Fergus Allerton: Investigation (equal); methodology (equal); validation (equal); writing – review and editing (equal). Pawel M. Beczkowski: Methodology (equal); validation (equal); writing – review and editing (equal). J. Scott Weese: Investigation (equal); methodology (equal); visualization (equal); writing – review and editing (equal). Andreja K. Hrček: Data curation (equal); methodology (equal); resources (equal); writing – review and editing (equal). Felisbina Queiroga: Methodology (equal); validation (equal); writing – review and editing (equal). Luca Guardabassi: Methodology (equal); validation (equal); writing – review and editing (equal).