Skip to Main Content
Ask About Financing

What Are Some Common Cat Illnesses & Symptoms?

What Are Some Common Cat Illnesses & Symptoms?

Numerous cat illnesses and their symptoms may be worrisome or even fatal if left untreated for too long. Our Torrance vets offer insight on signs and symptoms to be aware of. 

What are some common cat illnesses?

Here are some diseases to be aware of as a cat parent. Be prepared to see your veterinarian if required, especially since ill cats prefer to isolate themselves instinctively. The following are 3 prevalent feline diseases and associated symptoms.

Upper Respiratory Infections

Your cat's upper respiratory tract — their throat, nose, and sinuses — can become infected with viruses and bacteria. Often passed around in multi-cat households and shelters, cats may contract feline herpesvirus and feline calicivirus through something as basic as sharing a food or water bowl. 

They can spread this illness to other cats in the same manner they do to humans, or by sneezing or coughing. It can also be transmitted during grooming.

Symptoms include:

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


If a cat doesn't produce sufficient insulin to balance blood sugar or glucose levels, they develop diabetes mellitus. Left untreated, it may lead to several serious symptoms, such as:

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

If diabetes is poorly controlled, the disease can shorten a cat's lifespan and lead to numerous health problems such as nerve disorders. It may also result in severe emergency situations. Treatment can include insulin injections and will be focused on managing this condition. 


Cancer can be caused by uncontrolled cell development, which can damage a variety of organs and cells in a cat's body. The disease first starts to develop within a cell, before it attaches to tissue below the skin and potentially spread to other areas. 

A common contributor to cancer is Feline Leukemia Virus, which cats can be diagnosed against. Other causes include environmental toxins. If caught early during a physical exam, your vet may be able to treat cancer. 

Symptoms include:

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

Depending on whether the tumor is caught and diagnosed early enough, the type of cancer and its extent, specific location within the body, etc., whether an effective treatment plan can be developed, and other factors, a number of treatments such as radiation, surgery, and chemotherapy may be attempted. 

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 Harbor 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).

Do you suspect your cat is sick? Our vets are experienced in diagnosing and treating many common illnesses and conditions. Book an appointment at Harbor Animal Hospital today.

New Patients Welcome

New Patients Welcome

Harbor Animal Hospital is accepting new patients! Our experienced vets are passionate about the health of Torrance companion animals. Get in touch today to book your pet's first appointment.

Contact Us

Book Online (310) 328-3733