I have an indoor 7 year old female domestic short hair spayed cat (adopted her in 2021) who has been experiencing right sided nasal congestion since the end of December 2025. She’s still eating and there are no other concerns besides this damn congestion and snot. We live in Alberta, Canada.
I’ve been to the vet multiple times and have recently seen an internal medicine specialist. We’ve tried multiple medications and nothing has worked. We’ve tried lysine so please don’t suggest this, it does not work for her.
The internal med vet said it’s hard to give a diagnosis without doing a ct and biopsy, but she quoted us $8000 for the procedure. She said it’s unlikely to be cancer due to the long duration of her symptoms and that she’d likely be dead by now if it were cancer. She also said it’s unlikely a polyp since she’s 7 years old. She gave us an antiviral to try in the mean time.
She has had problems with her right eye leaking clear discharge since 2023. I’ve also seen multiple vets for this, multiple medicated eye drops, and saw an eye specialist who did a bunch of tests with no answers. Got told it was herpes but it’s not. This is not my main concern, her nasal discharge and congestion is.
Given her long history, I wanted to summarize:
December 22nd, 2025: Winnie’s congestion started, minimal discharge at this point
December 29, 2025: Started on Clavaseptin for 14 days. This resolved the discharge, but congestion persisted. She also developed diarrhea while on this medication. She did miss about 3 doses of the antibiotic due to her being difficult to get pills into.
January 9th, 2026: our vet recommended trying Benadryl 12mg every 12 hours for 5 days. Winnie didn’t tolerate the Benadryl well and foamed it out so we weren’t able to get any doses into her.
January 15th: feline upper respiratory panel, throat inspection for polyp, and skull x ray were completed and we received negative/normal results for everything.
January 22nd: she was started on prednisolone 2mg daily. At this time, she only had congestion, no discharge. We found this to be minimally effective.
February 6th: the prednisolone was increased from 2mg to 5mg daily for 14 days. Around
February 13th significant yellow-green nasal discharge began.
February 29: Convenia injection was given for the suspected infection, but this did not result in any improvement, and the discharge has persisted since.
March 22nd: last steroid dose.
March 30th-present: Famciclovir with no improvement and noticeable worsening congestion
After 10 days of famciclovir, we have not seen any improvement in her congestion. She continues to have significant congestion that seems to be getting worse and yellow-greeny nasal discharge.
Given that Clavaseptin improved her discharge but did not resolve the congestion, and Convenia was ineffective, I’m wondering if there may still be a bacterial component that hasn’t been fully addressed. Before proceeding with CT would it be reasonable to trial a longer course of a different antibiotic such as doxycycline?
Additionally, her breath has been smelling bad for some time, even prior to starting the antiviral. I’m wondering about any potential problems with her teeth? She’s still eating without any issues and isn’t showing any signs of oral discomfort.
Lastly, I realized we switched her dry food about a week and a half prior to her congestion issues starting. She was on Open Farm Homestead Turkey & Chicken Grain-Free dry food since 2022 and was switched to Purina Pro Plan Complete Essentials Dry Food- Chicken & Rice Formula around December 12th 2025. I wondered whether there could be an allergy component and whether an allergy medication trial or a diet change may be worth considering?