Why is my cat lethargic and acting strange after vet vaccines?

Thank you for submitting your question regarding Lily. Vaccines can result in lethargy. I would discuss this with her veterinarian at her next appointment. She may benefit from some pain medication in case she is uncomfortable after her shots. If she experiences vomiting after her vaccines, this is a sign of a reaction. Her veterinarian will need to know this information as well. Even if she is indoor only, vaccinations are necessary for her. I hope this information helps!

Poor Jasper! The timing of his signs certainly correlate with his vaccine. Not eating and lethargy (as well as vomiting, diarrhea, facial swelling and hives) can be signs of a vaccine reaction. Vaccine reactions are uncommon, but do happen. If Jasper still isn't eating by later today, I would give your vet a call to have him rechecked. Some vaccine reactions require steroids and/or antihistamines for treatment.

Hello and thank you for your question. I hate to hear that Covid-Max (love that name!) is not feeling well. It's possible that Max is having a vaccine reaction. These generally occur within 24 hours and can range from severe lethargy, fever, swelling of the face to collapse. He may have a fever today which is not uncommon with a vaccine reaction (though not always present). I recommend to call your veterinarian right. They may want to exam Max again to check for signs of a reaction and to treat him. Additionally, if this is a vaccine reaction, they will take precautions in the future to decrease the potential for another reaction. This may include giving him an anti-histamine before his vaccines, spreading out his vaccines or giving him a steroid. I hope this helps and that Max starts feeling better quickly! Please feel free to post any additional questions.

Hi, Sweet Ginger is looking quite sleepy in the pic. Signs you could still see as a reaction to the cat vaccine are : lethargy (already showing), fever, loss of appetite, vomiting ,diarrhea, Swelling (a lump) and/ redness around the injection site. These signs are short lived around 24-48 hours post vaccination. If you do notice a small lump at the site of the injection that can appears also several days after just monitor it should reduce and disappear in the next few weeks. Hope this helps

This sounds like a side effect of the vaccine, it's not super common but i'v seen a few cases already and this usually resolves within 48-72 hours. your vet could give her pain killers for a couple days if her condition seems to be really bad.

I'm so sorry that Noushmc isn't feeling well. Pain at the injection site and mild lethargy are very common with vaccinations and considered normal since the vaccination is stimulating the immune system. It usually lasts 1-2 days and will resolve on its own. If Nouschmc is not eating, is vomiting or it lasts more than 2 days, I would contact your veterinarian. Good luck! I hope she feels better soon and that was helpful. Thanks for using Petco Pet Education Center, formerly Petcoach.

That is very unusual that he is not better and I think he should have a work up to try to figure out the cause. Your vet can run some bloodwork to rule out potential medical problems. Most cats are usually better within a few days after having a reaction to a vaccine and three weeks seems like a very long time. If your vet can't do a work-up then you should go to a different vet for a second opinion and work-up. So sorry that he is having this problem.