Blood tests for cats are a valuable tool in most veterinary clinics. Our Clarksville vets explain why blood tests for cats are important and what each test result might mean.

Blood Tests For Cats

You may be unsure what your veterinarian is looking for when they suggest blood work for your cat. Even the most seasoned pet parent may be terrified of not knowing why their cat requires a medical procedure or what the results mean.

Below are some of the common blood tests done on cats and what they tell the veterinarian.

Complete Blood Count (CBC)

A CBC measures and examines a cat's blood cells. It gives the veterinarian a wealth of information. Some of these include:

  • Red blood cell (RBC) counts, proportions, and health - RBCs carry oxygen, iron, and other nutrients around the body.
  • White blood cell (WBC) counts, proportions, and health - WBCs help fight inflammation, infection, cancer cells, and parasitic intruders.
  • Platelet counts and health - Platelets control blood clotting.

A CBC can tell a veterinarian if a cat is anemic, dehydrated, fighting off inflammation or an infection, and whether your cat has internal bleeding.

BUN & Creatinine

BUN and creatinine are two blood chemistries that are routinely measured as part of larger blood panels. A high BUN level may indicate dehydration, kidney dysfunction, or a liver problem.

Creatinine levels are more closely related to kidney function. High levels indicate that the cat's kidneys are having difficulty removing creatinine from the body and that kidney disease may be developing.

Alanine Aminotransferase (ALT) & Bilirubin

Routine blood tests frequently include blood chemicals like ALT and bilirubin. They are mostly indicative of liver health, and abnormally high levels usually indicate a liver problem.


Glucose, or blood sugar, is usually tested to see if a cat has diabetes mellitus, which causes a very high glucose level. Additionally, low blood sugar levels can provide a veterinarian with critical information about a cat's overall health.

    Feline Leukemia Virus (FELV) & Feline Immunodeficiency Virus (FIV)

    FELV and FIV testing in kittens is done on a regular basis throughout adulthood. It is critical to monitor your cat's health in relation to these viruses because they are potentially fatal and incurable once infected. You should also have your cat vaccinated for further protection.

      Thyroxine (T4)

      As cats age, their T4 levels are frequently checked. Cats frequently develop hyperthyroidism, which is indicated by an elevated T4 level. Cats with high thyroid levels may exhibit a variety of symptoms, including increased appetite, weight loss, eating non-food items, craving more human food, and frequent vomiting.


      Electrolyte levels, which include potassium, sodium, and chloride, can provide valuable information about a cat's health, including hydration and organ function, particularly kidney function. Electrolyte imbalances in cats can cause a variety of symptoms, including cardiac arrhythmias and muscle weakness.

      Why Your Vet Might Suggest Blood Work

      There a many reasons your vet might suggest bloodwork for your cat. Here are the most common reasons:

      It's your cat's first exam - We recommend blood work at the time of your cat's first exam because it helps us establish baseline health, check for any congenital abnormalities or potential concerns, and help us form an individual wellness plan for your cat.

      During semi-annual and annual wellness exams - Cat blood tests are usually recommended for all life stages from kittens to geriatric cats as part of their routine wellness checkups. These are extremely beneficial in our mature patients, as we often see cats' health and happiness return to normal when blood tests catch illness early. Cat bloodwork, along with other bodily fluids like urine, can help identify conditions the examination portion of a physical cannot.

      If a cat seems sick - Cat blood tests are suitable for cats that are not displaying any overt signs of illness, disease, or injury, but are acting abnormally.

      Before surgery - Cat blood work is used to determine the general health of the liver, kidneys, and other organs, which helps a veterinarian select the safest form of anesthesia. Bloodwork can also help determine the surgical risk level in all cats, especially elderly or injured patients.

      What Can Be Learned From Your Cats Blood Test

      The results of feline blood tests are essential to helping veterinarians diagnose and treat medical conditions both within the blood itself, as well as in organs such as the kidney and liver. During a blood test for cats, various chemicals in the bloodstream are analyzed. Some examples are:

      • Cat blood tests can indicate a deficiency in albumin levels, which indicates a possible liver issue because albumin is produced in the liver, or intestinal or kidney issues as albumin can be lost if these are diseased.
      • Blood tests for cats can detect abnormal hormonal-chemical responses to environmental and internal stimuli, which indicates a potential issue with the patient's endocrine system.

      Once we've established a connection, we can order any additional feline bloodwork or procedures needed to diagnose and treat the disease. In this regard, feline blood tests are extremely useful tools in a veterinarian's toolbox for detecting, identifying, diagnosing, treating, and, ultimately, preventing illness or disease.

      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 your cat is displaying abnormal behavior, maybe a blood test is in order. Don't hesitate to contact our Clarksville vets to schedule an appointment today.