The global burden of ectoparasitic infestations is exacerbated by the lack of licensed vaccines, meaning safe and effective ectoparasiticide drugs are vital to their prevention and treatment. However, adverse clinical consequences of treatments for ectoparasites affect thousands of cats and dogs in the UK each year. The unpredictable outcomes of these treatments in some animals can be associated with undesirable consequences and there is a lack of knowledge surrounding their use. This article discusses indications of the major classes of ectoparasiticides used in small animal practice and highlights the types of adverse drug reactions associated with the parasiticides used to treat ectoparasite infestations in dogs and cats. Overall, the incidence of adverse drug events reported in relation to ectoparasiticide use, compared to the total doses administered globally, is small. The potential consequences for animal and human health of not using ectoparasiticides is likely to be more serious than the current rate of adverse drug reactions being reported. The benefits of protection from ectoparasite infestations will therefore outweigh the potential consequences of adverse events associated with such treatment.

Anna LJ Copland -

Hany M Elsheikha -