Common Cat Illnesses and Symptoms

It can be alarming if your cat suddenly seems to be under the weather. Our Danbury vets discuss some possible causes and symptoms of illnesses in cats.

What are some common cat illnesses?

There are a number of illnesses that could affect your feline friend. At one point or another, it may be necessary to visit your veterinarian. Here are some of the most common illnesses in cats and the symptoms they may display.

Upper Respiratory Infections

Your cat's upper respiratory tract consists of their throat, nose and sinuses. It is common for the respiratory tract is can become infected with viruses and bacteria. Respiratory tract Infections are easily transmitted in areas with multiple pets and cats may contract infections such as feline herpesvirus and feline calicivirus through something as basic as sharing a food or water bowl. 

Cats can transmit these viruses by sneezing and coughing around each other or by grooming one another.

Some symptoms of these viruses are:

  • Gagging, drooling
  • Runny nose or clear/colored nasal discharge
  • Fever
  • Cough
  • Sneezing
  • Decreased or lost appetite
  • Congestion 


 Just as in humans, cats require stable blood sugar or glucose levels. If a cat doesn't produce sufficient insulin for this purpose they could develop diabetes mellitus. If left untreated it may lead to serious symptoms, such as:

  • Thirst
  • Increased urination
  • Increased appetite (as the body cannot use the energy in food) or loss of appetite
  • Vomiting
  • Dehydration
  • Motor function problems
  • Coma
  • Death

It is crucial that diabetes in your cat is appropriately controlled, otherwise, the disease can decrease your cat's lifespan significantly and cause various health problems such as nerve disorders. which could result in emergency situations. Common treatment may include insulin injections with a focus on managing this condition. 


Cancer is an uncontrolled growth of cells that can negatively affect a wide range of organs and cells in a cat's body. The disease begins by developing within a cell before attaching itself to the tissue beneath the skin. From this point, the cells have the potential to continue to grow and spread to other areas of the body.

One of the common causes of cancer in cats is Feline Leukemia Virus. This type of cancer is entirely preventable as it is possible for cats to receive a vaccination for this virus.  There are many other possible causes of cancer in cats which can include environmental toxins. If caught early during a routine vet checkup, your vet may be able to treat cancer. 

Symptoms include:

  • Lumps or bumps that change in size or shape
  • Sores that do not heal
  • Odor from the mouth
  • Unexplained bleeding or discharge
  • Marked increase or decrease in appetite
  • Chronic weight loss
  • Difficulty urinating or defecating

Treatment options for cancer in your cat will vary depending on how quickly it was diagnosed, the type of cancer, the specific location within the body, as well as many other factors. Some possible treatment options might be chemotherapy, radiation or surgery. 

What should I do if my cat is ill?

If your cat is sick and exhibiting any of the symptoms listed above, it's critical to bring them to the vet as soon as possible. At Noah's Ark Animal Hospital, we have an in-house laboratory, onsite pharmacy, and emergency clinic to provide your pet the care they need (help for after-hours emergencies is also available).

If you notice any of the above symptoms of illness in your cat it is recommended to contact your vet as soon as possible. Our vets at  Noah's Ark Animal Hospital have the use of a full in-house diagnostics lab as well as a pharmacy in order to provide the best possible care for your cat. 

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

If you are concerned that your cat may be displaying signs of illness book an appointment with our experienced vets at Noah's Ark Animal Hospital today.