Update to Responsible Use of Parasiticides Policy Position
31 October 2025
BVA, BSAVA and BVZS have updated their joint Policy Position (31st October 2025) on the Responsible Use of Parasiticides in cats and dogs to reflect new evidence which has emerged about the potential environmental impacts of these products.
Parasiticides are an essential component of small animal veterinary practice, providing protection against parasitic infestations, safeguarding animal welfare, and reducing the risk of zoonotic disease transmission. Since the Position was initially produced in 2021, further evidence from multiple sources indicates that some small animal parasiticides, including topical products, can contaminate the environment, with potential adverse effects on wildlife and ecosystems.
The Position also highlights knowledge gaps and emphasises the need to balance animal health and welfare, human health and the health of the wider ecosystem.
Recommendations
BSAVA, BVA and BVZS again worked together to ensure the updated Position takes into consideration the most relevant recent research. The update includes amendments to existing recommendations and the additional recommendation that where possible and reasonable, topical products should not be used on pets which are likely to swim or be bathed. This recommendation reflects recently published research – which has indicated that certain topical treatments may remain on the pet and pass into the environment through dog bathing and swimming for longer after application than previously thought – while acknowledging there will be some situations where their use is required in order to protect animal welfare.
The Position emphasises that veterinary professionals should always take a risk-based proportionate and targeted approach to prescribing medicines, including parasiticides, aiming to use parasiticides as little as possible but as much as necessary, depending on individual animal and owner circumstances.
Collaboration
The Position stresses the importance of collaboration across a complex stakeholder landscape comprised of government, veterinary professionals and manufacturers, and suggests parasiticide resistance monitoring can benefit by learning lessons from antimicrobial resistance strategies.
BSAVA President, Dr Julian Hoad MRCVS said: “Responsible use of parasiticides is integral to protecting pet health and supporting the One Health agenda. Recent research improves our understanding of how parasiticides can potentially contaminate the environment, particularly topical treatments. However, knowledge gaps remain including around the persistence of parasiticides in the environment and the potential for resistance to some products. As veterinary professionals, it is incumbent on us to minimise the potential adverse impact of parasiticides on the environment whilst protecting animal and human health.
“BSAVA supports tailored, targeted treatments which benefit pet health yet at the same time address concerns. Taking a practical and proportionate approach to use parasiticides to best effect, empowers owners to make informed decisions, including around water-based activities and grooming. However, given the complexity of the small animal landscape it is essential that all involved collaborate to address the key issues to protect our combined health and the environment we share into the future. Tackling this One Health challenge is a joint endeavour.”
British Veterinary Association President Dr Rob Williams MRCVS said: “The use of parasiticides to protect human and animal health and welfare is essential but it is vital they are used and disposed of responsibly to minimise their impact on our planet. With more evidence coming to light to suggest that our rivers and lakes can become contaminated with these products due to treated animals swimming in them or being bathed after treatments, it is clear change is needed.
“We already encourage veterinary professionals to take a risk-based approach to prescribing these products and we would now ask vets and clients to include the animal’s swimming habits in these conversations and, where possible and reasonable, to use alternatives to spot-on treatments if they can if they are likely to swim or need frequent bathing.
“As with any medicine, each animal – and human client – will have their own unique needs and these all need to be taken into consideration when deciding on treatments.”
British Veterinary Zoological Society President Dr Elliott Simpson-Brown MRCVS said: “BVZS is pleased to see the publication of this policy position on responsible use of parasiticides, as it acts as an important indicator of the focus now being applied to the broader responsible use of veterinary medicines and associated impact on the UK wildlife and ecosystems as a whole.
“As a Society comprising of a broad span of veterinary professionals, involving those working with native wildlife, BVZS is proud to have contributed to this policy position with BVA and BSAVA.”
One Health
Described as a “One Health problem of immense complexity,” the Position emphasises that the issue will require ongoing review as new evidence emerges. BSAVA Policy has been actively engaging with stakeholders and government departments to raise awareness of the effects parasiticides can have on ecosystems and the need to minimise these impacts, while recognising the health and welfare implications of parasite infestation in companion animals alongside the potential risks to human health.
Further resources
Joint Policy Position with BVA, BSAVA and BVZS on the responsible use of parasiticides for cats and dogs: https://www.bva.co.uk/media/6627/bva-bsava-and-bvzs-policy-position-on-responsible-use-of-parasiticides-for-cats-and-dogs.pdf
Joint 5 Point Plan produced by BVA, BSAVA and BVZS to help veterinary professionals practise responsible, risk-based use of parasiticide products for dogs and cats: https://www.bsava.com/wp-content/uploads/2023/04/BVA_BSAVA_BVZS-responsible-use-of-parasiticides-for-cats-and-dogs-the-5-point-plan.pdf
BSAVA Scientific Position Statement on parasite control: https://www.bsava.com/position-statement/parasite-control/
BSAVA library collection on parasiticides: https://www.bsavalibrary.com/content/parasiticides
Cross-government Pharmaceuticals in the Environment Group Roadmap, focussed on focus on topical parasiticide products for cats and dogs: https://www.gov.uk/government/publications/cross-government-pharmaceuticals-in-the-environment-group-roadmap