• The feline distemper vaccine protects your cat from a highly contagious, serious disease.cat image by Ivan Zhelev from Fotolia.com
  
  Feline distemper is also called feline panleukopenia, and it is a highly contagious, often fatal viral disease. While some cats display fever, vomiting and diarrhea, other cats simply die without manifesting many signs. Vaccination protects your cat from feline distemper, but be aware that vaccinations for feline distemper do have some side effects.
  
  

Lethargy

• After a feline distemper vaccination, a cat may be lethargic for a few days. It may be uninterested in food, or it might simply not have the energy that it did before. While this can be alarming behavior, it is also entirely normal. While the veterinarian should be contacted if the behavior continues, the lethargy will usually clear up in one or two days.
  
  

Anaphylactic Shock

• Anaphylactic shock is a very severe allergic reaction. While it is a very rare occurrence, it can occur after a feline distemper vaccine. They typically occur within a few minutes to a few hours, and some signs of anaphylactic shock include difficult breathing, panicked behavior and facial swelling. If your cat is showing signs of anaphylactic shock, call the veterinarian immediately.
  
  

Mild Fever

• Sometimes a cat will develop a mild fever after being injected with the feline distemper vaccine. This will usually pass in a day or so. The veterinarian may preemptively give the cat medication to keep a mild fever from happening.
  
  

Sneezing

• Some cats develop fits of sneezing for one or two days after their vaccination. This is entirely normal and will pass on its own.
  
  

Discharge

• Some cats evidence a watery discharge from their eyes or their nasal passages after they have been vaccinated against feline distemper.
  
  

Ulcers

• In very rare instances, a cat may develop nasal or oral ulcers after a feline distemper vaccination.