Thanks for the additional information.
I am very sorry to hear that Precious is not able to hold any of her food down so far and is not feeling well. Dilated pupils, vomiting, breathing heavily, and acting lethargic are all very serious symptoms therefore I can understand why you are very concerned at this point. Here are the most common causes of her symptoms at this point:
- As you mentioned eating something toxic is a very common cause, many plants can upset a cats stomach as can certain insects and possibly even an animal that was deteriorating that she ingested
- Eating something that has become stuck inside of her intestines or stomach
- Pancreatitis which is a uncomfortable inflammatory disorder of the pancreas
- A liver or kidney
disorder or infection
- An intestinal virus
Since her symptoms seem very serious at this point, I would always recommend taking her to a vet tonight to have a full exam and possibly an x-ray to make sure that there is not anything causing an obstruction in her intestines.
I am glad to hear that she is eating as this is a good sign, though if she continues to vomit the food back up then she really should be seen by a vet.
If you would like to give her something at home to help her with the vomiting then you can give her some pepcid AC. This is very safe for cats and can help relieve nausea in the stomach. The dose is about 2.5 mg or 1/4 of a 10 mg tablet every 24 hours. It is only available as a pill though which can be a little more difficult to give to cats.
Overall I do think that having her seen by a vet tonight would be best if possible.
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