Taurine Deficiency in Cats

Michael Kearley, DVM
By Michael Kearley, DVM on Dec. 8, 2023
A colorful cat licks their lips.

In This Article


What Is Taurine Deficiency in Cats?

Taurine is an essential nutrient (an amino acid, the building block of proteins) in cats. This amino acid can’t be made in their body because cats don’t have the enzymes needed. As a result, cats require taurine daily as part of their diet.

Taurine is found in most animal proteins like meat, liver, and eggs, and is easily obtained from naturally occurring prey such as fish, birds, and rodents.

Since 1987, taurine has been adequately provided in commercially prepared cat foods approved by the American Association of Feed Control Officials (AAFCO). Fortunately, as a result, taurine deficiency is not as common as it used to be.

Taurine has a wide range of essential functions throughout a cat’s body. It’s important for a cat’s heart, brain, and reproductive health. It’s necessary for vision and bile acid production, which aids in food digestion. When a cat is deficient in taurine—which often occurs only after months of eating inadequate levels—symptoms show up in these body systems.

Acutely, it is not considered a medical emergency, but over time, permanent damage can occur, resulting in blindness and even heart failure. Therefore, it’s important that as a pet parent, you ensure your cat is eating enough taurine in their food on a daily basis.

Symptoms of Taurine Deficiency in Cats

Symptoms usually develop only after months of not eating enough taurine, but typically include the following:

  • Eye damage with lesions that can lead to blindness—You may first notice your cat bumping into objects, seeming disoriented, having difficulty finding food/water bowls and toys, and showing reluctance to enter dark rooms or go up and down stairs. You may even see a greater sheen (reflectiveness) in their eyes.

  • Impaired reproduction—This may result in spontaneous abortion, infertility, low birth weights, and birth defects. Affected kittens may have stunted growth and development.

  • Heart dysfunction and dilated cardiomyopathy (DCM)—This can lead to eventual heart failure. Pet parents may see their cat having difficulty breathing, pale or blue gums, a weak pulse, generalized weakness, collapse, and even death.

  • Deafness

  • Immune deficiency, which may show as recurrent infections

  • Poor appetite

  • Exercise intolerance

  • Muscle atrophy

Causes of Taurine Deficiency in Cats

Taurine deficiency in cats is often the result of an inadequate diet without enough taurine. Such examples include:

  • Unfortified commercial diets

  • Home-cooked diets

  • Vegetarian diets

  • Dog food fed to cats

How Veterinarians Diagnose Taurine Deficiency in Cats

Diagnosis is often based on symptoms that are present and checking taurine levels of the blood. Feed can often be analyzed to determine if the taurine levels are high enough.

If vision problems are present, eye tests may be done, such as an electroretinogram (ERG), which can detect changes in retinal function. Cats with symptoms of heart disease will be screened for DCM through X-rays and echocardiography, where an ultrasound probe is used to look inside the heart.

Routine laboratory tests such as a complete blood cell count, internal organ function screening, urine testing, and testing for feline leukemia and feline immunodeficiency virus (FIV) may also be done.

Treatment of Taurine Deficiency in Cats

Treatment of taurine deficiency in cats requires supplementation with taurine, which may be lifelong but is typically only needed for a few months until improvement is noted in the cat’s symptoms.

The diet is often changed as well to ensure the cat is fed a complete and well-balanced diet, one approved by AAFCO, the organizational body that ensures the safety and quality of pet food and requires the correct levels of taurine in the feed. Your veterinarian can recommend a high-quality taurine supplement, but be advised that the quality of supplements can vary from manufacturer to manufacturer. Formula® V Taurine Tablets and Dyna-Taurine® liquid are labeled for use in cats.

When looking for the best kind of diet to feed your cat, consider that the commercial pet food minimum taurine requirement for adult cats is 25 mg/100 kcal for dry food and 50 mg/100 kcal for canned foods.

It’s important to note, however, that the requirements can vary individually, so be sure to speak with your veterinarian about the right amounts of supplementation for your cat.

Cats with heart disease, especially those in heart failure, will often be placed on medications, most of which will be for life.

There is no treatment for cats diagnosed with retinal damage and/or blindness, as these symptoms can’t be healed. However, supplementation is advised to prevent further damage from occurring.

Recovery and Management of Taurine Deficiency in Cats

The prognosis for cats suffering with a deficiency in taurine varies and ultimately depends on the symptoms the cat has. With supplementation, cats diagnosed with DCM have a good prognosis and can show improvement in as little as a few weeks and can go on to have a good quality of life.

Cats suffering with retinal lesions will have permanent damage, as will cats with congenital birth defects. Yet most cats can adapt to being blind and learn to rely on their other senses. At home, you can take certain steps to ensure a safe environment, such as:

  • Minimize moving furniture

  • Block off access to stairs and pools.

  • Keep the floor free from clutter

  • Keep your cat indoors

  • Apply padding to sharp edges and corners

Additionally, be sure to get your cat’s attention before approaching or petting her to prevent startling her. Voice commands can be useful when moving around the home.

Prevention of Taurine Deficiency in Cats

Fortunately, taurine deficiency is preventable. As cats require daily taurine supplementation and taurine is found in high quantities in animal protein, feed a diet with adequate sources of animal meat and byproducts, which the majority of AAFCO-approved diets contain.

Royal Canin®, Hill’s Science Diet®, and Purina One® all use highly digestible proteins and ensure all their products include taurine as part of their nutrient profiles.

Be sure to avoid feeding home-cooked diets, diets with excessive plant proteins, and commercially prepared dog food. These diets are often nutritionally unbalanced and don’t have enough taurine.

Taurine Deficiency in Cats FAQs

What foods are high in taurine for cats?

Most animal protein tissues such as muscle, heart, brain, and internal organs have high levels of taurine. Unfortunately, taurine is not found in plants.

How often do cats need taurine?

Taurine is a daily requirement for cats that can easily be met by feeding a properly balanced, high-quality commercial cat food.

What are the side effects of taurine deficiency in cats?

Taurine is important in heart, brain, and reproductive health and it is necessary for vision and bile acid production, which aids in food digestion. When taurine is deficient, heart disease, blindness, and spontaneous abortion can occur, among other symptoms.

Can cats have too much taurine?

Taurine is considered to be well tolerated, and its toxicity potential is low. Excessive doses could cause gastrointestinal upset. Be sure to speak to your veterinarian about the right dose and brand of supplement to use.

How does a taurine deficiency in cats relate to cardiomyopathy?

Taurine is thought to protect the heart by helping to regulate its ability to contract (pump) and save and make energy along with aiding in blood pressure regulation. Cats with deficient amounts of taurine can develop dilated cardiomyopathy, or DCM, which can lead to heart failure.

Featured Image: Chalabala/iStock / Getty Images Plus via Getty Images


Association of American Feed Control Officials. AAFCO cat food nutrient profiles. West Lafayette, IN, 2019.

Plumb, D. Plumb’s Veterinary Drug Handbook. 8th ed. Wiley Blackwell; 2015.

Why Taurine Is So Important for Cats and Dogs.” Royal Canin. October 2020.

Wilson, SA, et al. Evaluation of the nutritional adequacy of recipes for home-prepared maintenance diets for cats. Journal of the American Veterinary Medical Association. 2019;254(10), 1172-1179.


Michael Kearley, DVM


Michael Kearley, DVM


Dr. Michael Kearley graduated from the University of Florida College of Veterinary Medicine in 2013. He graduated with a certificate in...

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