Thursday, March 30, 2017

What does a cat rodent ulcer look like when it's new?

Maggie the cat looking out the window

I talk about cat rodent ulcers quite a bit on this blog, mainly because Maggie gets them frequently and has done so for all of her life. But it strikes me that I typically talk about these sores when they're in a late stage of development. When her ulcers are open and a little bloody, that's when they appear on the blog.

But in reality, many of Maggie's ulcers never erupt into painful, bloody sores. Much more frequently, she has a very mild form of ulcer that is--I've been told--not very painful. And with the right therapy, I can keep those sores from getting worse.

Maggie has another one of these issues now, so I thought I might show you what it looks like. Here she is in closeup. Look at her lower lip here.

Maggie the cat in closeup

See how half of her lower lip is white? Now, look closely at that white part. There's a tiny bit of black here. That's the ulcer.

Rodent ulcers are caused by an overactive immune system. And they respond as do most immune system problems with swelling. Maggie's little black lower lip is puffy in just one spot, so I can see it on the bottom of her face, peeping out through her fur.

Maggie's lip can stay in this phase for weeks. When they appear, an injection of Depo-Medrol, which is a steroid medication, can help to take the swelling down again.

Maggie has that vaccine quarterly as a preventive measure, but she often gets ulcers like this the week or so before her injection is due. Within a day or so of having that injection, the swelling goes back down.

In acute stages, ulcers like this are spectacularly bloody. Maggie has bled all over her fur, her food bowls and me when an ulcer has gone wrong. And those open lesions can cause scarring--and some have tied that scarred skin to cancer.

So spotting an ulcer when it's early and new is pretty vital, even if seeing it is a little hard.

Rodent ulcer closeup

I look for lips that are so puffy that they shine, like this. Lips shouldn't be shiny. And when I see it, off to the vet we go.

I hope this helps some of you out there who are also dealing with rodent ulcers. There are plenty of ways to treat them, in addition to Depo-Medrol, but you have to know what they are in order to get your cats the therapies that are needed.

If you're using another therapy with your cat, I'd love to know about it. Drop me a note in the comments, okay?

And if you want to see what the next phase of these ulcers look like, see this example of a top-lip ulcer, and this example of a middle-of-the-mouth lesion. Both look pretty scary, but both healed just fine. If you're dealing with this, there is hope!


  1. Great information. Haven't had to deal with this with any of mine - yet!

  2. Ernie gets this regularly. The vet dermatologist thinks it's seasonal allergy related. Ernie doesn't get the depomedral shot...he has when it's been really bad...but steriods aren't always good for cats. He takes an antihistimine and prednisolone when it's really bad. Most of the time, like Maggie, it doesn't bother him much.

    1. I used to let Maggie's sort of take their course. But she's had at least two that were deep inside her mouth/creeping down her throat. That scared me, and it scared her vet too. We tried an antihistamine, but it didn't help her at all. We both felt like the benefits of steroids--in her case--outweigh the risks. But you're right. Steroids aren't always the right choice for all cats.

  3. We are familiar with these too. Phoebe was on atopica, but I stopped giving it to her because a side effect is appetite loss. I didn't see it making a difference anyway, it is for allergies. We go to the vet Monday so we will see what else we can do. I am glad you have something that works for

  4. Wow--I had never heard of ulcers in cats! Good to know what to look out for!

  5. Whoa! I read about these in 15 and Meowing. I hope I never get one.

  6. We've had a few cats over the years at the shelter who had rodent ulcers. Thank you for this really informative post, Jean. I am glad you are so diligent with working to manage Maggie's.

  7. We use homeopathic remedies against ulcers and they work purrfectly fine. We can't give you a name of a remedy, as it is dependable on more aspects, but you could check out a homeopathic vet. Healing Pawkisses <3 <3 <3

  8. I was researching rodent ulcers online and found your blog. I have a kitty that has been suffering for almost a year now from this. It started after I left her at a friends house last summer when I had to take a trip overseas. She was fine but when I brought her back home the lip swelling began. I'm positive that it's becasue she was stressed about me leaving her and I feel terrible... I tried everything under the sun from antihistamines to antiseptic gels to colloidal silver to steel/glass bowls etc but the only thing that seems to work is cortisone. She started on oral prednisolone and the swelling went down at fist but didn't disappear completely so the vet and I came to the conclusion that a depomedrol shot was necessary. She got the shot yesterday and I've noticed she's been "sleepier" than normal. I'm hoping that one shot is all she'll need even though from what I'm reading she probably will need more. Anyways I just wanted to comment and thank you for sharing this information. You have some cute kitties :-). Silvana

    1. I hope your sweet kitty heals up. And I know it's easy to say, but please try not to blame yourself. You're helping kitty now, and that's what matters.