Are there any risks associated with vaccinations?

On the whole, everything that we're injecting into an animal does come with associated risks. Most of the time it's perfectly benign and actually helps much more than it hurts. The leptospirosis vaccine, in particular, often causes a mild vaccine reaction with some swelling or pain at the injection site. Thankfully, that’s a pretty simple fix. Just call your veterinarian, and they can prescribe pain meds as needed.

Yeah, unfortunately, the honest answer is yes, of course, there is. I mean, you're putting a foreign substance into a living creature. Animals are going to react differently, no different than people might do. So, yes. It's hard to predict which vaccine they're going to react to because, again, every animal is different, but the most common ones that we'll see reactions to are things like rabies and sometimes lepto that I mentioned earlier.
You know that old expression, an ounce of prevention is worth a pound of cure. I am one of those guys that really like to vaccinate my own dogs, because I would much rather take that rare chance of them having a vaccine reaction but know that they're protected, because I can tell you, as a veterinarian, I've seen too many puppies die of parvovirus right in front of me that could have been prevented with adequate vaccination.

Unfortunately, there's always a potential for an adverse reaction with any vaccine. This is certainly true for people. It can be true of a shingles vaccine, a flu vaccine, and a COVID vaccine for people. There is a potential risk of having an adverse reaction. Generally speaking, we see three types of adverse reactions to vaccines, not just in puppies. This is with the dogs and cats. We very rarely see adverse reactions in cats. The most common one, even though it's not very common at all, but it is the most common of the three, is injection site discomfort, much like what a lot of people experience when they get a vaccine. Generally, we'll suggest that they take some children's aspirin, depending on the weight of the dog, to help relieve some of the discomfort going on. Much less commonly, we will see dogs that might get vomiting or diarrhea from the vaccines.

Although, sometimes, with puppies, that might be from car sickness or the stress of this strange new environment that they're in and they've never been exposed to before. Third, and certainly the least common, we give lots of vaccines every year, and we may only see two or three per year of this type of reaction where dogs actually may get a true, what we call anaphylactic reaction, where they get some swelling in the face or little bumps all over their trunk or their sides. That's an extreme case, and we do have the medications on hand to be able to treat those dogs.