I apologize in advance for the length of this post, and some stuff that is a little gross, but we've recently been down this road with our oldest, Sugar, who just turned 18. Correction, we are still on this road!
So that is why I wanted to respond to you, we are playing the guessing game with her as well. I am sharing everything just to see if anything in this story resonates with you. Cerenia is just one thing that we tried.
The whole time we've had Sugar, about 19 months now, she has had a profuse vomiting problem [ETA: She is not diabetic]. We have 6 cats currently, and have another 7 who have passed on -- in other words, we've seen a lot of medical issues over the years. I've never seen vomiting like this before. Not smooth brown liquid like Jones had or white foam like Tracey's other cat (although we've seen that a lot from 4 other senior cats we've had with kidney disease), not right after eating, and she doesn't scarf her food down quickly.
She would just be sitting there minding her own business, and (sorry this is gross) in the blink of an eye she projectile vomits everything in her stomach in a spray from where she is sitting to about 4 feet away. No retching before hand, no looking like she is going to vomit or bring up a hairball. Bang, vomit. about every 3 days. Although her stool looked ok, often the field of vomit would start right outside her litterbox. Here's what we've been through.
Bloodwork first, including an SDMA test. Early kidney disease. Started her on omeprazole (Prilosec). Didn't affect the vomiting, but still giving it daily anyway since we know she has CKD.
No idea what she was eating before we adopted her, so for months we tried elimination diets, novel proteins, to see if it is food allergy. No luck.
Metronidazole for its anti-inflammatory effects in case it is something like IBD.
Maybe chronic constipation or megacolon? Perhaps the vomiting was after straining in the litter box, even though we didn't always witness the vomiting? We did an xray and she was backed up, so she had an enema and then we added Miralax daily for that. Still no help with vomiting. So we added cisapride for a couple of months, no help with the vomiting. She HATED the compounded cisapride, so left that out and it made no difference. But monitoring of her litter box showed much more regular stool once we got the right dose of miralax...too much and we didn't see diarrhea, but she was dropping tiny little turds in her bed so we reduced it and now the poop department is good and we don't think it is contributing to the vomiting.
Hairballs? Added hairball treats for a month. No difference.
So then in addition to the Miralax and omeprazole, we start trying to just address the vomiting without knowing what is causing it (if that makes sense). Got a cerenia injection at the vet with no other changes just to see what it would do, and she was good for about a week, which was a record. But then the vomiting started again, so we started cerenia tablets. Didn't get the same affect as the injection, still vomiting every few days, but tried cerenia for about a month to be sure. No help.
So then we started two things at the same time, which I am telling you so that you are aware that I do NOT know which one is helping. We started a half tab of Ondansetron (which we put in an any gel cap with her omeprazole to easily pill her just once) every evening about 1 hour before her dinner. But we also added 100mL of fluids every evening. With her getting miralax every day, which pulls fluids in from your body, even though I water down her wet food 50/50, we thought it was a good idea. Now, I know that Ondansetron is supposed to be fast acting and has a very short half-life, but my vet liked the idea that it addressed vomiting in a different fashion. From a human page: "Ondansetron hydrochloride is a new serotonin receptor antagonist that is effective in preventing emesis associated with cancer chemotherapy. The antiemetic effect appears to be exerted through a peripheral vagal blocking within the gastrointestinal tract, as well as an inhibitory effect within the chemoreceptor trigger zone (CTZ). " I won't pretend to understand all of that, but it was this last part about the CTZ, a trigger within the brain that induces vomiting, that made her think about the immediateness of her vomiting.
Long story longer, so now she is still on 1/2 tablet Omeprazole and 1/2 tablet of Ondansetron daily an hour before dinner, and 1/8 tsp miralax twice daily in wet food at breakfast and dinner. Knock on wood...it's been two months now (anti-jinx, anti-jinx) and no vomiting. I am skeptical of the Ondansetron actually helping based on what I know about it, but I am also unwilling to stop it right now because we were all miserable fighting the vomit -- she had to be confined to one room to keep an eye on her ins and outs and also to minimize the damage. The whole room and bed was covered in fabric painting tarps, we were doing laundry all the time, and eventually that carpeting is still probably going to have to be ripped out. Even though she
seemed ok both immediately before and after vomiting, that can't feel good, right?
IF our two month "streak" eventually ends, I'll probably remove the Ondansetron and wait and see if the frequency of vomiting increases or the vomiting was just a one-time event to try and definitively determine if Ondansetron is making any difference. Sugar is a champ at getting fluids, purrs the whole time and doesn't leave my lap even when we are done, it's good for her CKD, so we will continue that and the omeprazole regardless. She's 18 so we aren't going to put her through anything like an endoscopy, or anything like that. Even when she was vomiting, she seemed very healthy and happy, and she continues to be one of the happiest and most outwardly loving cats I've ever had, from the very first night that she was in our house. She even gained some weight during this (?!?), she was a little underweight when she came to us.
All of this might not help at all, but I wanted to share just in case there's any tiny piece that resonates with what you are seeing because I know it is frustrating. I made the same comment about Sugar, that she is just fine
except the vomiting thing! Also this is an interesting article:
http://veterinarycalendar.dvm360.com/diagnostic-strategy-vomiting-dogs-and-cats-proceedings-0
I hope you can find something to help your kitty too.
