Distemper is a contagious, highly lethal, and almost incurable viral disease in dogs and other terrestrial carnivores. This study evaluated a new distemper treatment for dogs. Two healthy male dogs of mixed breed were prepared. A 1 000-dose vial of Newcastle disease vaccine was then diluted with 6 mL normal saline and 3 mL of it was injected into the cephalic vein of each dog, collecting 20 % of the blood volume 11 h later. Blood sera were separated and used as anti-Newcastle disease vaccine serum (ANDVS) to treat dogs suspected of having canine distemper. Dogs with confirmed distemper were grouped into the following seven treatment groups: 1- ANDVS; 2- ANDVS + Cotrimoxazole; 3- ANDVS + Penicillin-Gentamicin; 4- ANDVS + Cefazolin-Amikacin; 5- Cotrimoxazole; 6- Penicillin-Gentamycin; 7- Cefazolin-Amikacin. Then the fatality rate of dogs, association between distemper and sex, breed, age, and effects of distemper on hematological factors and vital signs were evaluated. The recovery rates in the ANDVS+ Cotrimoxazole and the ANDVS+ Cefazolin-Amikacin groups were higher than those in the ANDVS group (P < 0.05). Fatality rate was significantly different in distemper-positive and distemper-negative dogs. It is concluded that although ANDVS alone has no effect on the treatment of distemper, it can increase the recovery rate when combined with cotrimoxazole or cefazolin + amikacin as compared with the sole use of these antibiotics.