Natural Immune Support for Dogs & Cats

Written by: Dr. Jean Hofve, Holistic Veterinarian, DVM

The immune system is a complex network of highly specialized tissues, organs, cells, chemical messengers, and hormones. The lymph system and lymph nodes, spleen, bone marrow, and thymus gland all play a role, as do white blood cells, antibodies, and complement proteins.

Two Types of Immunity

There are two main types of immunity, innate and acquired.

Innate Immunity

Innate immunity is the body’s built-in defense system, and includes the skin, immune cells and organs, the linings of the gastrointestinal, urinary, and respiratory tracts, mucous secretions, and stomach acid. Innate immunity is a non-specific barrier against injury and infection.

Acquired Immunity

Acquired (also known as adaptive immunity) involves the immune system’s further defenses against specific invaders that are created as the body encounters different pathogens through exposure or illness. The immune system develops a memory of each disease it fights and is able to quickly recognize and defend against the pathogen the next time it appears.

Immune Support for Cats & Dogs

Healthy Diet

Diet is always the first line of defense and can help support your pet's overall health. If your companion is consuming highly processed food that provides only minimal nutrition and includes unacceptable ingredients, like toxins such as chemical preservatives, food dyes, texturizers, and other additives, your pet may not be receiving the proper nutritional support for healthy immune function.

Many people wait until their pet has a serious health matter or food sensitivity to finally change their pet's diet. Prevention is so much kinder and immeasurably more effective.

Feeding a varied diet that includes as much fresh food as possible and usually  entails more effort than scooping kibble out of a bag, but it can go a long way in supporting a healthy immune system in all animals. Healthy home made dog food mixes are a great way to get started with fresh food.

One of the benefits of a healthy diet is that it can support digestive tract health. Supporting and maintaining a healthy bowel inflammation response of the digestive tract is important to help support overall well-being.

Enzyme and probiotic supplementation can be another great way to ensure good health.

Stress and Exercise

Stress suppresses the immune system. Our pets can experience emotional stress from any number of sources, such as territorial disputes among pets (especially cats, which is why you should always properly introduce them in a multi-cat household), social stress, as well as noise and light pollution. Exercise can help manage normal stress and support the immune system. Moderate exercise has been shown to assist the immune system in humans and animals.

Weight control can also help; overweight dogs and cats may be much more susceptible to chronic issues. Proper diet and exercise are needed to support proper weight management.

Nutritional Supplements

Good quality natural vitamins for cats, especially daily multi-vitamin and mineral supplement, is a simple way to help support the immune system. Alternating between vitamin supplements for your pet can provide a more varied source of nutrients. For instance, we often give a regular multi-vitamin at one meal and a “greens” supplement at another meal.


Antioxidants for pets can also help maintain immune function. Antioxidants exist as vitamins, minerals, and other compounds in foods. Antioxidants act as scavengers and have been shown to aid in the elimination of unstable oxygen molecules called free radicals. Free radicals are highly reactive molecules that the body produces normally produces, however, if left unchecked, they can damage the body at the cellular level.

Vitamins A

Vitamins A, C, and E are the most commonly known antioxidants. Vitamin A is found in the liver and other animal tissues. It is abundant in fish liver oils such as cod liver oil. Carotene is a precursor to vitamin A found in plant material. Dogs can convert carotene to vitamin A by way of an enzyme found in the wall of their intestine. Cats, however, do not convert carotene well and must receive adequate vitamin A from animal sources. Vitamin A can help support the immune system by making white blood cells. Vitamin A also helps support skin health, which functions as a barrier to bacteria and viruses, as well as protects against shedding of cells into the urinary tract, which can lead to the formation of stones and other urinary tract symptoms.

Vitamin C

Vitamin C is the most abundant water-soluble antioxidant in the body and is manufactured in the liver and kidneys of dogs and cats. It is available from fresh or lightly cooked fruits and vegetables. Vitamin C may help protect against free radical formation and assits the body in combating environmental pollutants.

Vitamin E

Vitamin E is the most abundant fat-soluble antioxidant in the body. It is present in many foods including vegetable oils, cereal grains, greens, liver, and eggs. It is particularly helpful in decreasing oxidative damage, especially in fatty tissues.

Other powerful antioxidants include green tea, co-enzyme Q10, bioflavonoids, N-acetylcysteine, proanthocyanidins, quercitin, and curcumin (from turmeric).

Holistic Immune Support for Cats & Dogs


Cat's Claw

Cat’s Claw (Una de gato) can provide antioxidant and immune support. Cat's Claw can also help support normal circulatory function. Cat’s Claw is derived from a vine found in South America.

Chinese Herbs

Chinese herbs for dogs and cats are available in a variety of combinations and may help support a healthy immune system. Astragalus is one of the more commonly found Chinese herbs in immune formulations. Selecting the proper Chinese herbal formula is not always straightforward since a variety of conditions need to be considered before deciding on the best combination, so sometimes the guidance of a trained holistic veterinarian is important.

Green Tea

Green tea contains polyphenols that may help fight free radincals. Green tea can also support cellular health.


Curcumin, from turmeric root, is a very powerful antioxidant and supports a healthy inflammation response.


Echinacea can also help support a healthy immune system. It is a good choice for acute use, but it is not recommended for long-term use.

Medicinal Mushrooms

Medicinal mushrooms for dogs and cats such as Maitake, Reishi and Shiitake help support T-helper cells and can also help support the immune system. Cordyceps is a Chinese mushroom that provides antioxidant support and supports healthy cellular activity.



Colostrum is the first milk produced by mothers. Most colostrum commercially available is from cows. It can also provide immune system support.


This is by no means a complete list of herbs and supplements that can help support the immune system, but it includes many of the most common options. Providing extra support to assist the immune system through nutrition, herbs, and supplements can help your pet's overall health and well-being.

Additional Resources