Have Cat Questions? Ask a Cat Vet Online.
Greetings, I’m Dr. Peck, a small animal veterinarian in general practice. Hopefully I might be of some help. One moment while I reply…
Some causes of chronic rhinitis / sinusitis in cats are never completely resolved but instead should be thought of being "managed" as best as possible to alleviate clinical signs / discomfort as much as possible. This especially applies to autoimmune chronic rhinitis and nasal lymphoma or other cancerous causes of rhinitis / sinusitis.
Given you are taking care of Enzo for a friend, I'd suggest you continue medications as your friend informed you to do, as they were directed / prescribed by their veterinarian.
If it is ok with the owner of the cat, it is safe to instill 1-2 drops of little remedies phenylephrine drops in to / on to a cat's nose to help provide relief of nasal congestion. This medication is safe with steroids / antibiotics. It can be administered up to every 3-5 hours or less as-needed for nasal congestion.
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