Cytoxic drugs and neoplastic disease

The British Small Animal Veterinary Association (BSAVA) supports the use of cytotoxic drugs in the treatment of neoplastic disease in companion animals where there is evidence that such agents have a beneficial effect on quality of life, survival or both. However, many of these drugs have toxic properties which can have adverse effects on the animal, people in contact with the animal and the environment, and should be taken into consideration when undertaking chemotherapy.

The following risks should be considered when using cytotoxic drugs and planning treatment protocols:

• Risk to animal receiving chemotherapy
• Risk to the owner(s) of the animal receiving chemotherapy and any other people in close contact with the animal. For example, oral medications should be avoided in a household with pregnant or breastfeeding individuals, and an agent that might be present in saliva should not be used in a house with young children
• Risk to veterinary staff handling and administering drugs
• Risk to the environment through direct contamination from chemotherapeutics and from the excretions and secretions of the animal (including saliva, vomit, urine and faeces).

Cytotoxic drugs are hazardous substances, as defined by the Control of Substances Hazardous to Health Regulations (COSHH) and as such a documented COSHH risk assessment should be performed for these medicines if being used in practice.  Assessment of the hazards, potential harms, and the risks of those harms occurring should be made, and control measures set out in advance of use.

If providing cytotoxic treatment, both the practice and any clinicians involved in the patient care should ensure that they have the facilities and expertise to store and administer the treatment safely, to dispose of waste, and also to monitor and treat adverse events.

October 2026

Safe handling of cytotoxic drugs HSE

• BSAVA Client Information Leaflets
• BSAVA Medicines Guide – Cytotoxic section
• BSAVA Small Animal Formulary – Safety and handling of chemotherapeutic agents
• RCVS Veterinary Medicines Guidance – Cytotoxic drugs and COSSH Regulations (4.63 – 4.73)
• ACVIM small animal consensus statement on safe use of cytotoxic chemotherapeutics in veterinary practice

Hayes A (2005) Safe use of anticancer chemotherapy in small animal practice. In Practice (27); 118127. https://inpractice.bvapublications.com/cgi/reprint/27/3/118

Smith AN, Klahn S, Phillips B, Parshley L, Bennett P, Flory A, and Calderon R (2018) ACVIM small animal consensus statement on safe use of cytotoxic chemotherapeutics in veterinary practice. Journal of Veterinary Internal Medicine (32); 906-913. DOI.1111/jvim.15077