I recently had the privilege of attending a talk by a great veterinarian named Dr. Alice Wolf, an adjunct professor at Texas A&M University who is board certified in both feline medicine and internal medicine. She also happens to be a really great speaker. The topic of her presentation was feline vaccine protocols, which I’ve talked about in previous blogs, but she also brought up something worth focusing on: vaccine “reactions.”

Surely, you are familiar with the side effects of the vaccines that you get. The vaccination site is sore for a couple of days (or more), sometimes you feel terrible for a day or two afterwards, and in some cases, you may develop a fever. Soreness at the vaccine site makes sense – you got a shot there, so there is local inflammation. Other side effects, like malaise or fever, are actually good signs – they mean that your immune system is reacting appropriately to the vaccine.

For the most part, it’s fair to say that dogs and cats generally do very well after receiving their vaccines. But just like us, they can have side effects too, so it’s important to know the signs so you can contact your veterinarian if necessary.

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Signs of vaccine side effects in pets

Within a couple of hours after vaccines, your pet may show similar signs to those you experience post-vaccination, including fever, local discomfort/swelling, and decreased appetite. If your pet received a vaccine nasally (such as Bordetella), he may have nasal discharge or sneezing. These mild reactions are normal, but if they persist for more than a couple of days, or if your pet seems significantly uncomfortable, contact your vet.

Less commonly, severe side effects can occur due to “allergic” reactions. Vomiting and/or diarrhea, hives and facial swelling indicate a more severe reaction, and these occur, you should call your vet right away.

If your pet has experienced vaccine reactions before, be sure to tell your vet before additional vaccines are administered. She may choose to premedicate your pet to try to avoid side effects and might ask you and your pet to hang out at the office for an extra half hour just to make sure your pet does well after her vaccines.

If your pet experiences the mild side effects mentioned above, try not to be discouraged. Just like it us, it means the vaccine is doing its job. If you are ever concerned about your pet’s vaccine reaction, be sure to talk to your vet about it.

Mar 19, 2012
Pet Health

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