Cat with Pneumonia throwing up mucus

Four and a half days ago I took my 13 yr old cat in to the emergency vet clinic because he was suddenly lethargic, had difficulty walking and was not even interested in his favorite treats. He had a 104.8 fever, was diagnosed with FHV, pneumonia, poor circulation and some as-of-yet unknown variety of heart disease (suspected Hypertrophic cardiomyopathy). His heart is also not where it should be but is pretty far off to his left side and may be limiting the function of his lung on that side. Needless to say, he has a lot going on that complicates treatment. Despite all of of that, the vet said his breathing was strong and they felt confident that he could be treated at home. They had to sedate him for treatment, but they gave him antibiotics and gave him subcutaneous fluid injections. They suggested careful monitoring and a regimen of 125mg of Amoxicillin and Clavulanate every 12 hours. 10 hours later his fever peaked at 106 and we took him in again, but it’s been consistently around 102 for 36 hours now. We are now 4.5 days later and while he has his mild ups and downs, he is hydrating well, eating well enough for his activity level, resting breaths are at 20-26/min, his circulation is good, and other than resting more than usual he is behaving like his usual self most of the time. Today his appetite declined a little, he threw up some thick mucus, ate some of his favorite food, and threw it up along with a lot more clear mucus. He’s going in for a check up with our regular vet in 4 days, but I’m wondering if I should be especially concerned about it, or if it’s a good sign that the fluid in his lungs is at least draining (even if it is into his stomach). He isn’t coughing, wheezing, doesn’t have fluid coming out of his nose, or doing anything indicating he’s having difficulty breathing. It’s hard to keep my cool with every little thing since it’s tough to talk with cats, so any advice would be muuuuch appreciated.

Hello!  I'm sorry - it sounds as if you and your boy have been having a tough time.   Most recently, he has been sick - I'm unclear whether the 'mucous' is clear fluid coming from the GI tract, with vomit (eg following stress), or whether he's coughing up clear secretion from his nose and lungs. Particularly given that he is so ill in general, if your cats case has changed then it is worth getting in touch with the vet,  if only to establish their vital signs and how soon they propose a check, because we're all different.  Best of luck and please let us know how things go.

Sometimes, if there is mucous on the lungs and drugs help to break it up, the pet will then be able to cough it up more easily, which is helpful.  However, you should always run it by your professional.