Cat pain when eating

- 17-year-old neutered male cat, Turkish Angora mix, 4.7 kg.
He has occasional vomiting, currently controlled with treatment. No diarrhea and no weight loss. Location: Spain

Hi, I’m looking for advice about my cat’s case because I feel like I’m running out of options.

My cat was recently diagnosed with Intestinal low-grade lymphoma. He is currently on chemotherapy and corticosteroids. So far, he has no digestive symptoms, and his bloodwork is normal (he gets bloodwork every two weeks). I’m not writing this post because of his lymphoma, but I thought it would be useful to write it.

For the past few months he seems to be in pain when eating and often refuses food. Since around February his eating has gotten noticeably worse, although I first noticed something odd back in November (he was chewing to the side).

Now, when he eats, he moves his head side to side, drools slightly, spits out food (especially kibble), and sometimes makes a very unpleasant noise. Some days are better than others, but overall it’s inconsistent. He rejects both wet food and kibble, although he often approaches the food, smells or licks it, and then looks at me as if expecting something else. Apart from these symptoms and his diagnosis he’s pretty healthy, he asks me for food, not hiding, sleeping well, etc.

Things I’ve tried so far:
- Switching to smaller kibble.
- Adding water to soften the food.
- Slightly warming the food in the microwave.
- Cooling the food in the fridge in case cold helps with pain.
- Trying many different wet foods (textures and flavors). He tends to drink broth but leaves the solid pieces.
- Trying different proteins: chicken, turkey, duck, goose, pork, beef, salmon, quail, etc.
- Making homemade broth (he liked it once, then refused it afterward).
- Offering foods he used to love before his diagnosis (even if not ideal nutritionally), in case it was psychological.
- Blending food to make it smoother.
- Changing bowls, feeding on plates, the floor, even by hand.
- Changing feeding locations.

I’ve taken him to multiple vets because I suspected a mouth issue. He has had a CT scan and full-body X-rays. Nothing significant was found except some weird teeth, which were removed and healed well. However, his eating behaviour hasn’t improved at all after the extractions.

At this point, vets are only suggesting anti-inflammatories, which don’t seem to help and feel like a temporary patch rather than a solution. Prednisone (which he is already taking for lymphoma) also doesn’t improve his mouth discomfort.

I’m starting to wonder if this could be something more complex that isn’t showing up on tests.

Additional context:
- He already has a veterinary nutritionist (who actually suggested I seek more opinions), but he’s not following his diet well because he keeps rejecting foods unpredictably.

Medications tried:
- Buprenorphine (0.3 ml, twice): made him very sedated, he wouldn’t even get up to eat.
- Amoxicillin (after dental extractions): no improvement.
- Onsior (2 weeks post-extraction): no effect.
- Prednisone 5 mg (current, for lymphoma): no effect on mouth pain.
- Famotidine (for suspected nausea/vomiting before lymphoma diagnosis): no effect on eating issue.
- Mirtazapine (topical): increases appetite, but he still eats sideways and his ear becomes very red, so I can’t use it daily.

My current vet feels out of options and has only suggested more unusual tests (like gastric emptying studies), but even he doesn’t recommend doing them right now because it would be very stressful for the cat. I’ve also went to three different vets, no one has been able to give me a diagnosis or an effective treatment.

Does anyone know what this could be? Thank you.