When I noticed fast breathing and extreme tiredness in my adult cat, I consulted a veterinarian. They advised taking three antibiotics for three days. It has been two days since the final day of antibiotics, and he is less tired than before with no compromise in eating his food. He loves to eat, but his breathing is still fast. There are no other bad symptoms like nasal discharge, coughing, or anything else—just fast breathing and tiredness. The breaths are deep and fast, not shallow and rapid. So, is it an emergency since the condition is not worsening?
Hi there. I couldn't advise you specifically on whether this is a concern or not. Doctors have to make decisions based on physical exam findings and and diagnostic testing to find out what's going on. Now, this may be something as simple as an older cat that is sleeping more deeply (or purring perhaps? it's been known to be confused with rapid breathing). But ruling out a lower airway respiratory condition or heart condition can't be ruled out without the right imaging, like x-rays or an ultrasound. Cats can hide and tolerate things like this extremely well. If 3 days of an antibiotic exhibited no change, perhaps that means an infectious cause is less likely. But not all antibiotics work for all airway infections either (there can even be a difference between upper and lower airway infections) and it's hard for me to comment further on what such a short antibiotic course was expected to achieve (other than seeing if it helped and extending it further if it did). Overall, if what you're seeing is abnormal or a change for your cat, I wouldn't make assumptions about it being stable just because it hasn't worsened in 5 days. If a full physical exam has not been performed (I wasn't sure if consulting a vet involved a full visit or only a conversation) that should be considered, along with survey x-rays of the chest.