How can you tell if your cat has a weakened immune system? And is there any way to strengthen their immune system?

Has your cat lost interest in playing? Is your furry friend listless and constantly retreating to its cosy corner for a nap? Do you have the feeling your cat has been sick more often than normal lately? If this sounds familiar, it’s possible your cat’s immune system is out of balance. When a cat’s defences are down or compromised, it means their immune system is weakened. And without a stable immune system, they’ll be more susceptible to infections

Find out how you can help strengthen your pet’s immune system.

Understanding your cat’s immune system

Your cat’s immune system is like a protective shield that protects them from diseases and fends off bacteria, germs and viruses. In fact, your cat has a whole armada of substances and cells working constantly to protect it. These cells are always at their posts; their motto is “a danger recognised is a danger averted”. In other words, they’re forever scanning the things trying to get past the body’s barriers. The only things they let through are things that won’t harm your cat. Anything they classify as threatening will trigger a red alert: the bulkheads will close and your cat’s defences will be activated.

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How you cat’s immune system works

When your cat has an intact immune system, it will function like a knight’s armour, leaving no spot unprotected. Your cat’s defence mechanisms are concentrated on certain areas and they’re also closely interlinked and interlocked. In other words, these guards work very closely together. When an alarm is triggered in one place, they ramp up the defences everywhere else in the body, too. All posts receive the warning and quickly take up arms. Any intruders are then identified and ultimately destroyed.

Reminder: There are two types of defence mechanisms:

  • nonspecific defense: This is an innate defence mechanism. It protects “non-specifically”, that is, in a general and less targeted way. But it reacts quickly to a variety of known invaders.
  • specific defense: The special or “specific” defence mechanism emerges over the course of your cat’s life. The feline immune system will remember certain pathogens and defend itself accordingly so as to fight them off. This means double protection against pathogens!

Your cat needs these vitamins to build and maintain its immune system

In order to build and maintain a strong immune system, your cat’s food should contain a sufficient amount of vitamins A, B, C, D, E and K. Vitamins C and E, in particular, are believed to support the immune system thanks to their antioxidant properties and by preventing the formation of free radicals. But don’t forget, there’s no one-size-fits-all solution! The vitamins¹ your cat’s going to need will always depend on the type of cat and its overall living conditions. Also: Make sure you don’t overdose your cat’s vitamin intake!

¹Source: VGL Publishing AG (2023): “Vitamine für Katzen Vergleich 2023. Die besten Katzen-Vitamine im Vergleich” (German only). Online at Vitamine für Katzen Test & Vergleich » Top 10 im September 2023 , accessed 11 September 2023.


The more vitamins the better?


High-quality cat food will likely already contain sufficient vitamins, among many other things.

Please don’t give your cat any supplementary vitamins without first consulting a veterinarian!

Recognising when your cat has a weakened immune system

When your cat’s immune system is weakened, its defence mechanisms won’t be able to disarm pathogens as efficiently as they used to.
This means your cat will likely get sick more quickly. Cats with chronic diseases and those who recently had an operation, illness or infection will be particularly affected. The defences of younger and senior cats are also more susceptible to attack. You’ll usually be able to tell if you cat has a weakened immune system by recognising and identifying certain symptoms:

  • Loss of appetite
  • Complaining
  • Diarrhoea
  • Vomiting
  • Fever
  • Susceptibility to infection
  • Fatigue

Strengthening your cat’s immune system in everyday life

How can you strengthen your cat’s immune system? The first thing to do is find out why your cat’s immune system is weakened in the first place. There can be several reasons for this. Are they suffering from an allergy or do they have some kind of infection? If so, their immune system will have gone into overdrive to fight it. Or have they recently had an illness or medical procedure? You cat’s age will also play a role. Both very young and very old cats have fewer defences. For example, even though kittens get antibodies from their mother’s milk, their immune systems won’t be fully developed until they’re older.


  • Emotional or physical strain
  • Incorrect feeding
  • Infection
  • Lack of exercise
  • Stress
  • Injury

Cat exercise

Cats need lots of movement, because the only way to keep your kitty healthy and fit is by making sure it gets enough exercise! If your cat doesn’t get enough movement, their muscles will eventually atrophy, plus they won’t get the mental stimulation they need. Always make sure your cat gets plenty of exercise! Movement not only challenges and sharpens your cat’s senses; it also stimulates their metabolism, builds up their muscles and strengthens their cardiovascular system. In other words, more exercise and movement will make your cat healthier but also more emotionally stable.

IMMUNITY BOOST: Exercise strengthens your cat’s immune system, because the number of antibodies your cat produces will increase, but also because the killer cells responsible for defending their body are more active during exercise than when at rest!

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Healthy cat nutrition

A cat that weighs more than 15-20% of its ideal weight is considered overweight. Heavy cats often have a weakened immune system, which is why fat cats are more susceptible to severe illnesses and disease. With the help of a diet plan that controls calorie intake, you can take a step-by-step approach to getting your cat used to a healthy diet. The “BODY CONDITION SCORE” will provide you with orientation in terms of figuring out your cat’s “ideal body weight”.

Download here

Avoiding stress in cats

Let’s face it, some cats are super chill. They deal with changes in their everyday lives relatively calmly. But other cats will get stressed out and react nervously to anything that’s unfamiliar to them. Always make sure your cat has a place to retreat to when they’re feeling stressed. When cats are insecure or afraid, they usually react by fleeing, so if you set up a sanctuary where they can feel safe and secure, it will improve the situation and help avoid stress. Make sure it’s their place alone, somewhere that’s always safe and waiting for them when they’re in distress. This is the best way to avoid stress in cats.

Making sure your cat gets enough sleep

Just like humans, cats strengthen their immune systems when they sleep. If they don’t get enough sleep, their immune cells won’t work as effectively as they could. And when immune cells aren’t functioning effectively, their protection against pathogens will automatically be limited. Sleeping is important not only for your cat’s physical health, but also for their emotional well-being. Kitties tend to choose their sleeping place on their own, and they might even choose a different spot each time. Where and how a cat sleeps depends on certain factors and says a lot about them and their state of mind. Take a closer look and see if you can discern some kind of pattern!

Strengthening your cat’s immune system using home remedies

Are you interested in using tried and tested remedies rather than some chemical potion to boost your cat’s health? Wonderful! It’s possible to strengthen your cat’s immune system using home remedies you make yourself. The ingredients usually involve conventional foodstuffs found in an average home, or medicines that contain ingredients that are purely herbal in origin. For example, if you use them correctly, plants can have a healing effect on your cat. In fact, plants are like natural boosters for your cat’s immune system.

Propolis for cats

Propolis for cats is used in veterinary medicine. Thanks to its antibacterial and antiviral effects, this bee product is mainly used to fight inflammation and help heal certain wounds. But propolis can also help to improve an animal’s general well-being and strengthen their immune system. Cats with weak immune systems can take propolis in the form of drops and powder, but also periodically in the form of a vaccination.

Echinacea for cats

Echinacea inhibits the growth of free radicals while also increasing the body’s own defences and supporting your cat’s overall immune system. Thanks to its antibacterial and analgesic effects, this perennial plant is also used to heal wounds and fight inflammation. Echinacea can be administered as a powder or an alcohol-free liquid. Since many cats aren’t exactly enthusiastic about being given any kind of liquid, you can also just mix a small amount of Echinacea powder into your cat’s food.

Cat cress

Cat cress is the name for fresh herbs that can boost your cat’s immune system with essential oils, iron, folic acid, minerals, calcium and vitamin C. Varieties such as watercress, garden cress and nasturtium are also suitable for cats. They can be grown on your windowsill or in your garden. In small quantities, these herbs can be a valuable food supplement, helping to have a positive effect on health.


Before you offer your cat any kind of home remedy, you should always check with your vet first to find out if it’s even suitable for felines.

Your vet will also tell you the appropriate dosage and timeframe in which to give your cat the remedy!

Feline medications and supplements – Which ones makes sense for your cat?

Pet stores often offer medications and supplements designed to help keep your cat healthy by strengthening its immune system. But does it make sense to give your cat supplements in addition to their regular food? Or is this just an extremely lucrative business that mainly benefits the supplements makers themselves? Let’s take a closer look at the various medical products and supplements and see whether these cures can have a positive influence on a cat’s immune system and actually help to strengthen it:

Food supplements for cats

Any high-quality store-bought cat food that’s appropriate for your breed of cat will usually cover your cat’s needs and give it all the proteins, fats, carbohydrates, minerals and vitamins it needs. Food supplements can help to provide your cat with additional nutrients, especially in particular situations, for example, when their defences are weakened and they need a little extra support. Your vet will know what’s best for your cat and can recommend a suitable food supplement.

Multivitamin pastes for cats

Multivitamin pastes are intended to provide your cat with additional vitamins. However, as already mentioned above (“Your cat needs these vitamins to build and maintain its immune system”), please exercise caution when administering vitamins to your cat. If you give them too much, it can be harmful to their health! You should also take some time to look at the precise ingredients, as some pastes² contain unhealthy additives.

²Source: (2023): “Vitaminpaste-Katze Vergleich 2023. Vitaminpasten-Katzen-Vergleich: Die besten Produkte”, online at 8 beste Vitaminpasten-Katzen Test & Vergleich 2023 » 3 Top Produkte! ( , (German only) accessed 11 Sept. 2023

Food supplements for senior cats

For older cats to stay healthy and feel the best they can, they’re going to need a different food intake than when they were young. They don’t need food loaded with calories for increased energy needs; instead, senior cats need food that contains vitamins and proteins that are appropriate for them at this stage in their lives. In this case, special food supplements can help their immune system, metabolism and musculoskeletal system.

Immune treatments for cats

There are such things as immune treatments for cats that boost their immune system and help better prepare them for certain situations. For example, these treatments can be useful when moving from one season to the next, when your cat’s coat changes and during various processes of healing and recovery. Pets that are ill or getting over an illness are sometimes able to recover more quickly when they’re given an immune treatment consisting of proteins, micronutrients and vitamins.

Strengthening your cat’s immune system with injections

Senior cats and cats that are weakened or suffering from an illness can also be taken to the vet for injections designed to strengthen their immune system. These medications are injected at pre-determined intervals and work to strengthen your cat’s own defences. The injection stimulates their body’s natural defences, thus strengthening the entire immune system. There are a number of advantages to the process of administration by injection: the active ingredient can be individually dosed and its impact is faster and more precise.

Strengthening you cat’s immune system using homeopathy

Whether homeopathy helps strengthen your cat’s immune system or not is a matter of faith. Cat owners who swear by conventional medicine might frown upon homeopathy and choose other remedies. But those of us who believe homeopathy works will consider it a great alternative. In that case, individual essences or specifically composed mixtures might help to build up your cat’s defences.

FAQs – Strengthening your cat’s immune system

How can you strengthen your cat’s immune system?

The best way to boost your cat’s immune system is by making sure your feline friend gets sufficient exercise, has a healthy diet, avoids stress and gets enough sleep. Some plants can also have a healing effect; if used correctly, they can act as natural immune boosters.

Do cats have strong immune systems?

Healthy adult cats have strong immune systems, but senior cats and kittens have fewer defences. For example, despite the antibodies they get via their mother’s milk, kittens’ immune systems are not yet fully developed. The defences of senior cats also weaken with age.

When is your cat’s immune system considered to be weakened?

Your cat’s immune system will be weakened if the cat suffers from an allergy or if it’s picked up some infection. Your cat’s defences will start operating at full speed when it’s fighting off an illness or after undergoing a recent medical intervention.

How does a vitamin deficiency manifest itself in cats?

Vitamins are important. If cats consume too few of them, they might develop a vitamin deficiency, which can lead to a number of health problems, including apathy, anaemia, weight loss, digestive problems and neurological disorders.

Does it make sense to give cats supplements?

Food supplements can provide your cat with additional nutrients in particular life situations. For example, your cat might benefit from extra vitamins when their defences are weakened or when their body needs more support than usual.

Is it possible to strengthen your cat’s immune system naturally?

You can strengthen your cat’s immune system naturally. For example, you can use natural remedies with ingredients drawn from purely herbal sources. Certain medicinal plants can also support your cat’s immune system and function like natural immune boosters.

Can you use globules to strengthen your cat’s immune system?

Homeopathic globules are small white pellets that have become increasingly popular as a healing method not only for human beings, but also for cats. For cat owners who believe in homeopathy, this form of therapy is the preferred way to strengthen their cat’s immune system.