Because the cat already carries the feline distemper virus in its body before deworming, but it has no apparent symptoms, and it belongs to the incubation period of feline distemper. Due to the side effects of feeding anthelmintics, a series of symptoms of cat plague appear. The deworming medicine itself does not carry any feline distemper virus, it just becomes a trigger.

Symptoms of feline distemper:

1. When a cat has just begun to be infected with feline distemper virus, the feline distemper virus invades the lymphatic system and the symptoms are not obvious. When feline distemper virus (FPV) enters the cat directly through the oral or nasal mucosa and becomes infected, it enters the bloodstream 2 to 7 days later.

2. Feline distemper virus enters the blood from the lymphatic system. In the early stage of the feline distemper virus outbreak, the cat’s symptoms will be obvious, such as poor energy, loss of appetite, drooling, vomiting, and fever (40 ~41.7℃), some cats may even have abdominal pain and exhibit an unnatural bent back posture. At this time, they must be sent to the doctor in time.

3. 1-2 days after infection, the cat's vomiting begins to become frequent, the vomitus slowly changes from yellow-brown to yellow-green, and the diarrhea slowly changes from sticky to watery or watery. Blood in the stool. At this time, the cat may start not to eat, and there will be mucus flowing out of the facial features.