A paper published in September discusses the clinical course of permethrin toxicosis in cats, and examines whether methocarbamol treatment relates to improved morbidity and outcome. Permethrin toxicosis is a particular issue in cats, as they show increased sensitivity to pyrethroids. The study found that in most cases (89%) toxicosis was caused by owners inadvertently applying dog spot on products to their cats. Insecticide products intended for use in dogs can contain 45-65% permethrin, whereas products suitable for cats contain concentrations at less than 0.1%.
The most common signs of permethrin toxicosis reported in the study were tremors and twitching (90%), hypothermia (39%), seizures (30%), tachypnoea (25%), abnormal mentation (18%), ataxia (16%), hypersalivation (11%) and mydriasis (10%). Treatments included whole body bathing (85%), along with supportive care, sedatives and muscle relaxants. Some cats (5%) required general anaesthesia. The survival rate was 100%.
Permethrin toxicosis should be treated by supportive care, dermal decontamination and anti-convulsant drugs and muscle relaxants. In this study, methocarbamol was administered to 67% of cats, which had a shorter hospitalization period compared to that of cats untreated with methocarbamol. Intravenous lipid emulsion also has a role in the management of severe permethrin toxicosis but was not used in this study.