Even if you become one of the estimated 12 million Americans to contract lice each year, the family dog is safe – human lice feed exclusively on human blood. Human lice can't colonize pets or wild animals and do not transmit from them to humans. Nevertheless, dogs may be afflicted with their own lice species. If you and your dog have lice at the same time, rest assured he didn't get his from you.
One of two louse species typically afflicts dogs in the United States: the canine chewing louse (Trichodectes canis) and the canine sucking louse (Linognathus setosus). Chewing lice have heads that are wider than their thoraxes, while the heads of sucking lice are smaller than their thoraxes. Both species cause similar symptoms, including intense itching and scratching, matted hair, restlessness and hair loss. A number of flea treatments effectively eradicate lice infestations, and the Companion Animal Parasite Council recommends treating lice-riddled dogs with topical permethrins. Check with your vet to see which treatment is right for your dog.