• It is important to monitor a cat's health for signs of sickness.cat face image by Viktor Korpan from Fotolia.com
  
  A cat can be sick for many months before expressing any symptoms. It is important to understand the cat's mood and personality changes, since these can be key symptoms that something is wrong. As soon as the cat exhibits signs of sickness, seek immediate veterinary assistance.
  
  

Lethargic Behavior

• Recognize the normal behavior patterns of your cat. If your cat is normally energetic, but instead is sullen and lies down a lot, this can be a sign of sickness. Try to engage your cat in some of its favorite playtime activities. If it refuses to play or get up, then take the cat to a veterinarian to be checked out.
  
  

Discharge in Eyes

• Cat's eyes are normally very bright, shiny and moist. A cat's eyes can be one of the most striking features of this animal. The eyes should not have a dull appearance or have thicker than normal discharge coming from them. Take your cat into a dark room and then bring it back into the light. If the pupils cannot contract quickly in the light, this is also a sign of a sick cat.
  
  

Vomiting

• Cats normally swallow hair when grooming and need to cough up or vomit hairballs. If your cat is vomiting more than normal, like three to four times a week, this could be a sign of a more serious illness. Chronic vomiting could be an infection of the intestines or inflammatory bowel disease. If this condition is left untreated, it could have more devastating effects such as organ failure or an intestinal blockage.
  
  

Diarrhea

• Diarrhea is a sign that there is a problem in the cat's digestive tract. Severe diarrhea could cause dehydration. Blood or mucous may be present in the diarrhea, indicating parasites or other infections. A veterinarian will perform tests to check for parasites and administer the proper antibiotics to make sure infections do not persist.
  
  

Weight Loss

• Weight loss in a cat could be the first sign of sickness and should not be overlooked. If the cat has appetite loss or refuses to eat, this could be a sign of kidney failure or cancer. If your cat eats a lot but still cannot maintain weight, it may need to have its thyroid levels or blood pressure checked and monitored.