A healthy cat's eyes are usually clear, bright and wide, according to the Cat Health website. However, he may have discharge from his eyes for a variety of reasons. Discharge itself is not necessarily a major health concern; however, if it is accompanied by weakness, lethargy and loss of appetite, it may be a symptom of a serious respiratory disease.
Common Respiratory Diseases
The two most common respiratory diseases in cats are calicivirus and feline rhinotracheitis virus, otherwise known as FRV or herpes. Viruses cause both of these diseases, and cats often contract both of them at the same time, according to Animal Health Channel.
In addition to eye discharge, cats afflicted with herpes may sneeze or cough frequently, run a fever of up to 41.1 degrees Celsius, and have nasal discharge. Herpes causes complications in pregnant cats and often leads to premature, underweight kittens. Your veterinarian can vaccinate your kitten against the severest herpes symptoms, but there is no cure, and cats who contract herpes often carry the disease for the rest of their lives after symptoms abate. Some cats become malnourished because of refusal to eat during a herpes outbreak.
Calicivirus is a far milder disease than herpes, according to Animal Health Channel. The cat may display signs of lethargy and loss of appetite, eye discharge, runny nose, and sores in the nose or mouth. Some cats exhibit arthritis-like symptoms, such as pain while walking. Loss of appetite is much less severe in this disease; the cat does not usually run the risk of starvation.
A cat who is lethargic, weak and has eye discharge is obviously ill and should be seen by a veterinarian in order to prevent serious disease. Animal Health Channel states that it is often a good idea to isolate sick cats so that they cannot spread the disease among other pets. If your cat is an outdoor cat, keep him inside until he stops exhibiting symptoms. Your vet may prescribe antibiotics to help fight off the disease.
Occasionally, both of these diseases can lead to serious complications. Animal Health Channel states that some cats become anorexic as a result of appetite loss from herpes. Your vet may need to feed your cat intravenously in order to replace nutrients if she refuses to eat on her own. Calicivirus does not cause severe appetite loss. However, cats suffering from this disease can develop pneumonia.