There is one significant but I hope rare health risk when a cat plays with a dog and there must be millions cats playing with millions of dogs in the USA, UK and Europe and elsewhere. When I say “playing”, I mean being in close contact. I am unsure whether this is common knowledge. I don’t believe it is, hence this short post.
Permethrin is an insecticide. It is used in spot flea/tick prevention and treatments for cats and dogs in a range of commercial products.
As it has been widely publicized on the internet, you are probably aware that the concentration of permethrin in dog flea treatments is much higher than in the equivalent cat product. In the UK a dog spot treatment contains 74.4% permethrin (source: icatcare.com) whereas the Animal Poison Control Center (APCC) in the USA have found that 1 milliliter of 45% permethrin applied dermally (to the skin) to a 4.5 kg cat (about 10 pounds) can result in life-threatening toxicosis (disease caused by poisoning) (source: Journal of Feline Medicine and Surgery). Even one vial of cat flea treatment applied properly can poison a cat.
From those stark facts you can see that if a dog plays with a cat soon after being flea treated, the cat could get the chemical onto her skin (perhaps the ear where the skin in particularly thin and where the blood vessels are near the surface) and be poisoned.
Jill A Richardson DVM, writing in her role as a veterinarian at the ASPCA Animal Poison Control Center, mentions that in unpublished data from ASPCA and APCC from 1995-1997, a cat can become exposed to permethrin when playing with a dog on which the product has been placed.
For me this is a warning. The UK Veterinary Poisons Information Service reported for 1988-2006 that they had 1306 inquiries relating to permethrin poisoning and almost 50% concerned spot on treatments and of those 80% concerned cats.
Permethrin is very toxic and I am not sure that cat and dog owners are fully aware of the potential dangers. Some get dog products mixed up with cat products or careless apply dog treatments to cats and you couldn’t blame a person for letting their cat play with their dog or letting them lie next to each other but it seems that these activities should take place a good time after any flea treatment has been applied to the dog. A vet will advise on that.
Permethrin poisoning affects the nervous system. It attacks the method of nerve signal transmission which takes place with the help of sodium in the animal. The symptoms are nervous system related such as tremors and seizures. The treatment includes preventing seizures because they can cause permanent damage, I understand. A vet will prescribe an appropriate treatment such as methocarbamol (must be vet treatment) together with bathing with a mild dishwasher detergent solution (neither cold nor too warm) avoiding letting the cat get cold afterwards.