Q. My cat is all of a sudden breathing out of her mouth and sounds very congested, other then that seems normal and is eating normal
DR. CHRISTIE LONG, D.V.M., C.V.A.
A. I will reiterate what Dr. Edwards answered below. Mouth-breathing is abnormal in cats, and usually indicates respiratory (lung) or heart disease. Even when cats have an upper respiratory problem, such as a viral infection in the nose and sinuses, they do not breath out of their mouths. Possibly causes include feline asthma and heart disease. Although listening to the lungs and heart with a stethoscope can give us clues that there is a problem, ultimately problems are only obvious on x-rays. If your cat has not had chest x-rays, that is surely the next step.
LINDSEY EDWARDS MVB, BSC, IVCA
A. Mouth breathing in cats should always be treated as an emergency because cats will always breathe through nose and inability indicates major heart or lung disease. Contact your local emergency clinic