cat vaccine reaction

Question
I took my big, 9 year old cat for his booster shot for FVRCP  last week and he's been extremely sleepy and occasionally stumbled about like a drunk until this morning, when he seemed normal.  I'm taking him to the vet Monday, but has this reaction happened before?  He has no other symptoms of illness what so ever.  Thanks

Answer
Anne,

It is not unusual for cats to exhibit some side effects for up to 72 hrs after they are vaccinated.  These side effects tend to be lethargy, decreased appetite, mild diarrhea, pain at the injection site, and a slight fever.  Not knowing what day you vaccinated your cat, it's hard to say if what he's experiencing is within the time frame for side effects to happpen.  However, the stumbling about is concerning.  That is not a regular, expected rxn.  I actually know someone whose cat had the same side effect in her cat after vaccination. It stumbled around like it was drunk, with an ataxic gait, and couldn't quite get its balance.  It happened a little over 24 hrs after the vaccination, and caused her great worry.  Her vet had actually left on vacation, so she was left scared and worried and not knowing what to do.  

As it turned out, she ended up taking her cat in to another vet, and she was told her cat had reacted to some of the adjuvants (preservatives) in the vaccine, and was told to not ever vaccinate her cat again with anything that contained adjuvants.  So, it would be good to know if the vaccine your cat got had any preservatives in it.  

Good luck at the vet tomorrow.  I hope your kitty is feeling better by now.

Savannah