My cat vomited, is lazy, and won't eat. Should I be worried?

I would definitely keep an eye on him, and if he vomits again or doesn't want to eat still, schedule a vet appointment. Issues such as minor GI upset, underlying illness, hairballs or obstructions, parasites, etc can all be possible causes of vomiting, which is why it's important to have it checked out if it continues more than once. If Lando seems in any obvious distress or pain (vocalizing, pacing, attempting to go potty but can't, tender to touch, etc), then he should be seen sooner.

He may not feel like eating just yet as it is common it can take a day for his appetite to come back. I would let him rest today and let the medication start working. Try his food or even a little tuna in the morning. If he is still uninterested then you might want to get him rechecked for further testing

Yes, it is likely that Jack is upset about the addition of the new kittens. Introducing a new cat into the house is very stressful for an existing cat, especially old cats. I would try to tempt him to eat by offering him small amounts of boiled white meat chicken (no bones), or soaking his food in tuna juice or low sodium gently warmed chicken or beef broth. If he still won't eat with these methods, or it's close to three days since he last ate, I would take him into a vet right away. When a cat doesn't eat for three days or more, they become prone to a fatty liver, which is serious.

Felix just sounds like he feels terrible. Feed him a bland diet of boiled white meat chicken (no bones) in small amounts several times a day for a couple of days. Then slowly add back in his normal diet. If he refuses to eat the bland diet, he vomits the bland diet, develops diarrhea, stops drinking water, starts vomiting water, or becomes very lethargic, he will need to see a vet right away.

If he was recently at the vet for vomiting, and now is not eating or drinking anything, he should be seen again as this would make me concerned about the possibility of a foreign body, or pancreatitis, which would require additional therapy. If your vet didn't do x-rays or bloodwork at the previous appointment it's time to make sure there's nothing more serious going on. However, since your vet just saw Iron I would start by giving them a call with an update, in case they have other input based on their exam findings. Hope this helps and he feels better soon!

Hypothermic kittens can be much more sick than they let on. Vomiting can be caused by many things, including hairballs, food allergy, eating too fast, GI blockage, intestinal parasites, IBD, systemic disease (liver, kidney, pancreas, diabetes), among others. If the vomiting happens for more than 24 hours, or if Tom does not eat in that time, he needs to see a vet immediately. Continue to encourage him to drink water and eat canned cat food. You can use a heating pad on the low setting to help warm him up, but check often that it is not too hot as it is quite easy to burn their skin. You can leave the heating pad where he can sit on it, but if he moves away do not force him to go back.

Hi and thanks for using Petco Pet Education Center, formerly Petcoach! Sorry to hear about Simon. It's hard to say if you should be worried at this point but if the vomiting continues you will have to get him evaluated. Any sign of illness in a pet that persists or worsens needs to be evaluated by your veterinarian and re evaluated until the problem is resolved. Vomiting causes fluid loss and electrolyte loss and can lead to dehydration and weakness. Not sure if Simon is an indoor/outdoor cat but I would advise deworming him since intestinal worms are so prevalent. That is an easy thing to do to rule out intestinal parasites and should be done in all cases of gastrointestinal upset as long as the medication can be safely given and it is not vomited back up. Intestinal parasites are extremely common across the globe and account for the vast majority of vomiting and diarrhea cases. Other causes include inflammation, infection, dietary problems (including dietary indiscretion or eating things pets are not supposed to eat, food sensitivities/allergies), ingestion of foreign bodies or exposure to toxins, bacterial overgrowth in the gut, problems in the stomach, intestines, or even problems outside of the intestinal tract/stomach including pancreatitis, kidney/liver problems, metabolic disease (diabetes,etc), endocrine diseases (thyroid or other hormone problems), etc. A thorough history and physical exam with resultant diagnostics such as fecal tests, blood tests, and more imaging studies such as x-rays/ultrasound to try to determine what is going on. Good luck with Simon. I hope this resolves quickly with little effort.