Why is my cat agitated with dilated pupils after recent vaccinations?

Sometimes vaccines can result in some discomfort and lethargy, but usually only for 24 hours or so afterwards. If it has been longer than that since she was vaccinated it is unlikely to be due to the vaccines. If one pupil is consistently larger than the other that is abnormal however and I would recommend you take her back to the vet to be checked out.

This is called anisocoria, and it is a medical emergency when it occurs suddenly. Munna could be experiencing an abnormal reaction to the vaccines if this happened after he received them yesterday. I would have him seen by a vet immediately.

Poor guy! It could be a sign of pain or trauma from the event including head or neck trauma, or a side effect of pain medication. If he was bleeding did they find the source of it? Was he given any medications at the clinic (pain medication?) or to take home? Was he appropriate mentally there and then has declined? The problem with kittys getting attacked is that the attacker often shakes them while biting. This can create a lot of shear trauma under the skin that is initially not seen. If no meds have been given i would worry about pain or head trauma. I would recommend calling the clinic that saw him to report this change. The safest thing for these patients is for them to be hospitalized for monitoring because not all problems show up right away. If head trauma is suspected medications may need to be given for this. I hope this helps and thank you for using Petco Pet Education Center, formerly Petcoach!

Dilated pupils can be due to pain, nausea, anxiety, ingestion of toxic substances or neurological conditions. If she is eating and drinking and showing no other signs such as twitching or confusion you could provide plenty of fluids and bland food for 24 hours and monitor for any other signs. If she is otherwise unwell she should be seen as soon as possible

Horner's syndrome can result due to an ear cleaning if there was damage done to the ear during the cleaning, but it can also result from an ear infection, blunt force trauma, and disease of the eye among other things. If Munna had Horner's syndrome, you would see other symptoms such as drooping of the eyelid of the affected side, the third eyelid would be raised and appear red, and the affected eye may appear sunken. Moon should see a vet for this immediately. It's very serious when one eye suddenly is dilated while the other is not. The vet can diagnose what is causing this to occur, and can treat him for it. Please take him into a vet now.

I recommend calling a vet near you immediately, and having Linus seen, just to be safe. The epinephrine may have worn off by now, and in some cases allergic reactions require further care. If you notice any facial swelling, hives, or difficulty breathing, make sure to have him seen by a vet right away, as that could indicate a life threatening allergic reaction. I hope he feels better soon!

I am so sorry that your cat Milo is ill following vaccines. These are classic signs for a vaccine reaction, and therefore I recommend having him seen by your vet right away. If you vet is currently not open, then I would consider taking him to your ER vet to make sure he is stable and ok. He will likely get medications (antihistamine +/- steroids) to help combat the reaction. I do hope that your pet Milo is able to make a full and speedy recovery. I would notify your vet about this as soon as you can so that precautions can be taken next year when he is due for his vaccine boosters to help prevent this from happening again. Best of luck and take care!