Usually, arthropods which live on the host animal by sucking its blood. These include ticks, mites or mange, and fleas.
Itching or irritation. Upon parting of hairs or combing with a flea comb, parasites may be visible. With mites or mange, skin may appear red, inflamed, thick, or scaly. Ear mites may cause excessive or dark-colored wax, a foul smell, and swollen or inflamed ears which the dog may scratch or rub over other surfaces.
External parasites are transmitted from one infected animal to another or through contact with infected bedding, carpet, or vegetation.
Consult your veterinarian. Ticks may be removed easily with tweezers. Be sure you get their heads out of the skin, as the remaining pieces may cause infection. Wash the area where the tick was removed with a disinfecting agent. Fleas may be treated with oral prescriptions, dips, or powders. Mites or mange can usually be treated with dips like flea dips. Sometimes an anti-itching agent like Benadryl may be prescribed. Remember that when treating external parasites, the entire area that your dog has contact with must be treated as well.