In our practice, imiquimod has been used successfully to treat two forms of canine papillomavirus infection (Figure 4), feline herpesvirus infection, feline papillomas, feline Bowen's disease, and equine sarcoids. No side effects have been
seen so far. The drug may be helpful for solar dermatitis and precancerous solar-induced lesions in dogs and cats if the lesions
are localized. Irritancy seems to be an individual response, with horses and cats seemingly more sensitive than dogs. We are
applying it topically from two to four consecutive days a week at a dose of one packet (0.25 g) given over two or three days.
Generally we only treat some of the lesions and have seen untreated lesions also respond. It is available in boxes containing
12 doses for about $140, and a single dose can be dispensed to use for multiple applications.
Figure 4. Papillomavirus infection near a footpad in a dog (before therapy) that responded to imiquimod.
Heide M. Newton, DVM, DACVD
Craig E. Griffin, DVM, DACVD
Animal Dermatology Clinic
5610 Kearny Mesa Road
San Diego, CA 92111
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