My cat was put on a special diet for vomiting and diarrhea but the symptoms returned and he later developed constipation. What should we do?

Original Question: My 14-year-old indoor cat started vomiting with diarrhea about a year ago. He was given a prescription that helped for a short period of time and then his symptoms reappeared about a month later. His diet consists of urinary crystal prevention and the occasional can of EN Gastroenteric. About 3 months ago he was extremely constipated so we started adding about a half teaspoon of olive oil to his diet. He started vomiting again and having bowel movements every second or third day. He is very lazy about using the litter box for bowel movements and has always been a cat that bites. The vet needs to wear gloves to handle him during visits. We are contemplating putting him down which is supported by our vet as she is concerned about him biting our grandchildren. We would appreciate it if you could offer some insight into his condition. Thank you. - Teresa

My cat was put on a special diet for vomiting and diarrhea but the symptoms returned and he later developed constipation. What should we do? Apr 14, 2018

Hi Teresa,

Thanks for sending in your question.

I’m going to start this answer by saying I’ve been doing this for 14 years and I can read a lot into the situation. I’m sure there’s a lot of other things are happening that you’re not even telling me, both good and bad.

First off I’m going to make some assumptions. The fact that you’re using both a gastrointestinal food and a food that dissolves urinary crystals means that you have done some testing in your cat and you were treating conditions that you have found. So I know you’ve been doing some work, however, there is something really lacking in your question. I don’t see any discussion of diagnostic test that of been done recently and I think I know why that is. It could be because some time ago you did some diagnostic tests and he didn’t really reveal the reason for the vomiting so it isn’t being revisited now. My first recommendation is to perform some general blood work, a urine test, and maybe even an X-ray to see if that reveals the cause of the vomiting. I particularly recommend that you perform a test specifically for pancreatitis and a urine culture to rule out the possibility that there could be an infection in the kidneys. There are a lot of clients that I talk to who think that if they change the food, then the vomiting will get better and that’s usually not the case. It is always ideal to first figure out the cause of the vomiting before we jump to the treatment. Now I already know what you’re thinking, these tests will cost a fortune. Although what I’ve outlined is the ideal scenario, I’ll now start discussing things you can do that are not as costly.

There are a number of conditions that could be occurring. Your cat could have kidney disease, kidney infection, pancreatitis, stress, obesity, liver disease, gallbladder disease, inflammatory bowel disease, parasites, or other things I can’t think to list right now. You’ve given me some symptoms that could go along with so many diseases it’s difficult to know where to start. Most importantly, I don’t want this cat to be euthanized. Because most of these things can easily be treated, they just may be expensive and difficult to determine. I’m also not surprised that your cat is biting and aggressive. Many cats that are having some disease process will be uncomfortable and in pain. Even dental disease can cause cats to swallow kibble, throw them up whole, and be really aggressive because their mouth hurts. Usually, when I say these things, a client retorts by saying ‘no, you don’t understand, he’s always been like this’. I still think it’s worth determining a cause. I also think that stress is involved here and I wonder if your cat is overweight. An overweight cat can have stress, which can lead to vomiting and also aggression.

I strongly recommend that you work with your vet and have him undergo a couple of those tests. The very first thing I would do is blood work, as well as a urine and pancreatic test. I think this is a reasonable cost given that you get a tremendous amount of information and it may even instantly answer your questions. It could give you a course of action to solve the problem. If that is not something you want to move forward with then there’s a couple of things I would suggest. First, I would work on reducing your pet’s weight if in fact it is overweight. Next, if the vomit has whole kibbles in it, it could be due to dental disease and I would have you soften the food before feeding it. This could solve the problem and I would have him go for dentistry if it’s necessary and affordable. Next, you could speak to your veterinarian about a treatment trial based on your best guess as to what could be going on.

As far as the constipation is concerned, that’s an easy answer. I would recommend that you speak to your veterinarian about a diet to prevent constipation. There’s a medication that is safe and works as a stool softener and is very effective against constipation. Exercise and being at an ideal weight helps to prevent constipation. You could also ask about medications that help propel faeces down the track better in order to avoid constipation. I believe that adding a few of these things, especially the medication, will likely be successful in solving the constipation problem.

It is much more difficult to think of a treatment trial for the vomiting. You’ve already tried changing the diet and you’re currently using a gastrointestinal one. If the condition is inflammatory bowel disease, your cat may benefit from a hypoallergenic diet instead. If we think there is an infection, you could attempt a trial of antibiotics to see if that helps. Keep in mind that antibiotics can sometimes irritate the stomach and cause vomiting. This is one of the reasons why determining the cause of the vomiting is much more desirable than just performing a treatment.

Hopefully, some of these ideas will help you make a decision on your next steps. I really don’t think you should be at that point of euthanasia. Keep in mind that behavioural issues like what you have outlined can often be addressed by solving underlying medical conditions. It would be a shame if this cat were euthanized when it had turned out he was in pain.

Thanks for your question and good luck.

Dr. Clayton Greenway

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