# Cyclosporine for Cat Asthma and Atopic Dermatitis Cyclosporine for cats with asthma is not a standard or well-established treatment. It is used far more often for allergic skin disease, where it can reduce itching when steroids are not a good option. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Cyclosporine is an immunosuppressant that veterinarians use mainly for feline atopic skin syndrome, a pruritic inflammatory skin condition triggered by environmental allergens [1]. - It is not a first-line asthma drug. Inhaled steroids and oral steroids remain the standard for feline airway disease, and cyclosporine's role in asthma is limited. - Cyclosporine can be a steroid-sparing option for cats with skin allergies, which matters because long-term steroids carry real risks. - Blood levels vary widely between cats, and monitoring may be needed, especially at higher doses [2]. - Serious side effects and drug interactions exist, so this medicine should only be given under veterinary supervision. ## What Cyclosporine Is and What Veterinarians Use It For Cyclosporine is an immunosuppressant medication. In cats, its best-documented use is for allergic skin disease, particularly feline atopic skin syndrome (FASS). This condition was formerly called non-flea-induced, non-food-induced hypersensitivity dermatitis [1]. It is an inflammatory skin disease triggered by environmental allergens, and it causes intense itching [1]. Cats with this condition do not always scratch the way dogs do. Their reaction patterns include miliary dermatitis (small crusty bumps), eosinophilic granuloma complex (sores on the lips, chin, or skin), self-induced hair loss, and itching focused on the head and neck [1]. If your cat has been diagnosed with one of these patterns and other causes have been ruled out, your veterinarian may discuss cyclosporine. The broader term "feline atopic syndrome" has been proposed to cover allergic disease affecting the skin, gastrointestinal tract, and respiratory system [1]. That grouping is useful for understanding the disease, but it does not mean the same drugs work equally well in every part of the body. Skin allergies and airway disease respond to different treatment strategies. Cyclosporine is also sometimes used for other immune-mediated conditions in cats, and daily dosages of 5 to 20 mg/kg have been described for those uses [2]. That range comes from research settings and does not mean you should ever calculate a dose yourself. Your veterinarian decides the dose based on your cat's weight, condition, and overall health. For airway disease specifically, the evidence is thin. A review of treatment options for cats with eosinophilic airway inflammation found no current evidence to support one older medication as effective monotherapy [3]. That review did not test cyclosporine, but it shows how limited the treatment evidence is in this area. If your cat has asthma, the more established path involves inhaled medications and steroids. You can read more about that in [Feline Asthma: Diagnosis and Management](/knowledge/veterinary-medicine/clinical-methods/feline-asthma-diagnosis-management) and [Feline Asthma: Inhaler Therapy and Technique](/knowledge/veterinary-medicine/clinical-methods/feline-asthma-inhaler-therapy-technique). ## How Cyclosporine Works Cyclosporine blocks a specific step in the activation of T cells, which are immune cells that drive inflammation. By interfering with this pathway, it calms the immune response that produces itching and skin inflammation. This is different from how steroids work. Steroids suppress inflammation broadly and quickly. Cyclosporine targets a narrower part of the immune system, which is why it is often described as more selective. That selectivity is also why it takes longer to work. You should not expect the same fast relief you might see with a steroid. Because it dampens cell-mediated immunity, cyclosporine can make it harder for a cat to fight certain infections. One report described a cat on long-term cyclosporine and prednisolone that developed a severe mycobacterial infection, which was attributed to suppression of cell-mediated immunity [4]. This is uncommon, but it is the reason monitoring and prompt reporting of new symptoms matter. ## Dosing Basics for Cats Your veterinarian calculates the dose from your cat's weight and health. Never adjust the dose on your own, and never give a dose meant for another pet or a person. Cyclosporine for cats is typically given by mouth. It comes as capsules and as a liquid. The liquid form is often mixed into a small amount of food, but absorption can vary depending on how it is given. Follow your veterinarian's instructions exactly about whether to give it with food or on an empty stomach. If you miss a dose, do not double up. Give the next dose at the regular time, or call your veterinarian for guidance if you are unsure. If you are not certain your cat swallowed the dose, treat it as a missed dose and do not repeat it. Consistency matters with this medication. Blood levels build over time, and research in healthy cats given a high-dose protocol showed that levels rose significantly over the first several days of treatment [2]. That is one reason your veterinarian may want to check a blood level instead of assume the dose is right. ## Side Effects: What to Watch For Most cats tolerate cyclosporine, but side effects happen. Some are mild and pass. Others need a phone call or a visit. | Side effect | How common or serious | What to do | |---|---|---| | Vomiting, diarrhea, or poor appetite | Common and usually mild | Call your veterinarian if it lasts more than a day or two, or if your cat stops eating | | Lethargy | Common early in treatment | Mention it at your next visit, or call sooner if it is severe | | Increased thirst and urination | Can signal a metabolic problem | Call your veterinarian, especially if your cat is also losing weight | | Toxicity from high blood levels | Serious, seen with high doses or when levels are not monitored | Report any weakness, wobbliness, or unusual behavior right away | | New or worsening infections | Uncommon but serious | Call your veterinarian if you see non-healing sores, breathing trouble, or persistent fever | One case report described a cat that had been on cyclosporine and prednisolone for a year and developed diabetic ketoacidosis. Its cyclosporine blood level was above 2100 ng/mL, which indicated toxicity [5]. That cat had been on a relatively modest dose, which shows that individual cats can accumulate the drug in unexpected ways. This is why monitoring exists. If your cat has skin allergies, you may also be managing itching with other treatments. The article [Cat Allergy Treatment](/knowledge/veterinary-medicine/clinical-methods/cat-allergy-treatment) covers the broader options, including allergen-specific immunotherapy, which is part of standard management for feline atopic skin syndrome [1]. ## Who Should Not Take Cyclosporine and What Interacts With It Cyclosporine is not right for every cat. Your veterinarian will weigh the risks before prescribing it. Cats with certain infections should not take cyclosporine, because it suppresses the immune response needed to control them. Cats with a history of cancer, significant kidney or liver disease, or uncontrolled diabetes need careful evaluation. Cats that are pregnant or nursing should not receive it unless the veterinarian decides the benefit clearly outweighs the risk. Drug interactions matter with this medication. Because cyclosporine is processed by the liver, other drugs that use the same pathways can raise or lower its blood level. Tell your veterinarian about every medication, supplement, and topical product your cat receives, including flea treatments. Do not start anything new without asking first. The combination of cyclosporine and prednisolone deserves special attention. The cat in the case report was on both drugs when it developed toxicity and diabetes [5]. If your cat is on both, ask your veterinarian how often blood work and drug levels should be checked. ## Overdose and When to Call for Help If your cat gets more than the prescribed amount, call your veterinarian or a pet poison control hotline right away. Do not wait for symptoms to appear. Signs that suggest too much cyclosporine include severe vomiting, drooling, wobbliness, tremors, extreme lethargy, or collapse. These are emergencies. Go to the nearest veterinary emergency clinic if your regular veterinarian is closed. Bring the medication bottle with you. The label tells the veterinarian the strength and the number of doses your cat may have taken, which speeds up treatment. ## Cyclosporine for Cats With Asthma: What to Know If your cat has asthma, cyclosporine is unlikely to be the first drug your veterinarian reaches for. Feline asthma is an inflammatory airway disease, and the mainstays of treatment are corticosteroids, often delivered by inhaler, plus bronchodilators when needed. You can read about the signs and long-term management in [Cat Asthma: Signs, Diagnosis, and Long-Term Veterinary Management](/knowledge/veterinary-medicine/symptom-guides/cat-asthma). There is no strong evidence in published veterinary research that cyclosporine controls feline asthma. The evidence for cyclosporine in cats centers on skin disease and other immune-mediated conditions. If your veterinarian suggests cyclosporine for a cat with both skin allergies and airway disease, ask what it is expected to treat and what monitoring will be done. Some cats have both skin and airway allergies. Managing one does not automatically manage the other. If your cat is coughing or wheezing, that needs its own plan. ## Limitations and When to Contact a Veterinarian Cyclosporine is not a cure. It manages symptoms, and it works best as part of a broader plan that includes treating secondary infections, avoiding known allergens, and possibly allergen-specific immunotherapy [1]. Response varies from cat to cat, and some cats do not improve enough on it. Contact your veterinarian the same day if your cat: - Vomits repeatedly or cannot keep food or water down - Refuses to eat for more than 24 hours - Becomes unusually tired or weak - Develops new sores, swelling, or discharge - Drinks and urinates far more than usual Go to an emergency clinic now if your cat: - Collapses or cannot stand - Has trouble breathing or open-mouth breathing - Has a seizure or tremors - Shows severe lethargy that came on suddenly Schedule a routine visit if your cat's itching is not improving after several weeks, if you are struggling to give the medication, or if you notice gradual changes in appetite, weight, or behavior. Every cat is different, and only your veterinarian can evaluate your cat's specific situation. ## Frequently Asked Questions ### Does cyclosporine work for cat asthma? There is no strong evidence that cyclosporine treats feline asthma. It is used mainly for allergic skin disease and certain immune-mediated conditions. If your cat has asthma, ask your veterinarian about inhaled steroids and other standard airway treatments. ### How long does cyclosporine take to work for skin allergies? It usually takes several weeks to see meaningful improvement in itching. Some cats respond sooner and some need longer. Your veterinarian may adjust the plan if there is no change after a fair trial. ### Can I give cyclosporine with prednisolone? Sometimes, but the combination needs close supervision. A reported case of toxicity and diabetes occurred in a cat taking both drugs. Ask your veterinarian how often blood work and drug levels should be checked if your cat is on both. ### Is cyclosporine safer than steroids for cats? It depends on the cat and the condition. Cyclosporine avoids some steroid side effects, but it has its own risks, including immune suppression and variable blood levels. Your veterinarian will weigh both options for your cat. ### What should I do if my cat vomits after cyclosporine? Call your veterinarian. A single mild episode may not be a problem, but repeated vomiting, drooling, or refusal to eat needs attention. Do not give another dose until you have spoken with your veterinarian. ## Related Articles - [Cat Asthma: Signs, Diagnosis, and Long-Term Veterinary Management](/knowledge/veterinary-medicine/symptom-guides/cat-asthma) - [Cat Allergy Treatment](/knowledge/veterinary-medicine/clinical-methods/cat-allergy-treatment) - [Feline Asthma: Diagnosis and Management](/knowledge/veterinary-medicine/clinical-methods/feline-asthma-diagnosis-management) - [Feline Asthma: Inhaler Therapy and Technique](/knowledge/veterinary-medicine/clinical-methods/feline-asthma-inhaler-therapy-technique) - [Psychogenic Overgrooming in Cats: Stress-Induced Alopecia vs Flea Allergies](/knowledge/veterinary-medicine/behavior/psychogenic-overgrooming-in-cats-stress-induced-alopecia-vs-flea-allergies) - [Cat Flea Allergy Dermatitis: Symptoms and Relief](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-flea-allergy-dermatitis) - [Cyclosporine for Cats: Side Effects and Allergy Use](/knowledge/veterinary-medicine/pet-medication-guide/cyclosporine-cats-side-effects) - [Atopic Dermatitis in Cats: Symptoms and Treatment](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/atopic-dermatitis-cats-treatment) - [How to Treat Cat Asthma: Inhalers, Meds, and Attacks](/knowledge/veterinary-medicine/senior-and-chronic-care/how-to-treat-cat-asthma) ## References 1. [Feline Atopic Skin Syndrome - Integumentary System](https://www.merckvetmanual.com/integumentary-system/atopic-skin-conditions-in-dogs-and-cats/feline-atopic-skin-syndrome). Merck Veterinary Manual. 2. [Progression of cyclosporine A-blood levels in experimental cats receiving a high-dose treatment protocol](https://pubmed.ncbi.nlm.nih.gov/39479202/). Frontiers in veterinary science, 2024. 3. [The effectiveness of cyproheptadine as a treatment option for cats with eosinophilic airway inflammation](https://pubmed.ncbi.nlm.nih.gov/42757253/). Veterinary evidence, 2026. 4. [Quadruple co-infection with Mycobacterium tuberculosis complex and M. kansasii in a chronically immunosuppressed cat](https://pubmed.ncbi.nlm.nih.gov/42525188/). Veterinary research communications, 2026. 5. [Remission of diabetes mellitus induced by prednisolone in combination with cyclosporine toxicity in a cat](https://pubmed.ncbi.nlm.nih.gov/39042703/). Veterinary medicine and science, 2024. ## Further Reading - [Allergies of Cats - Cat Owners (Merck Veterinary Manual)](https://www.merckvetmanual.com/cat-owners/skin-disorders-of-cats/allergies-of-cats) - [Disorders Involving Anaphylactic Reactions (Type I Reactions, Atopy) in Cats - Cat Owners (Merck Veterinary Manual)](https://www.merckvetmanual.com/cat-owners/immune-disorders-of-cats/disorders-involving-anaphylactic-reactions-type-i-reactions-atopy-in-cats) - [American Veterinary Medical Association: First Aid Tips for Pet Owners](https://www.avma.org/resources-tools/pet-owners/emergencycare/first-aid-tips-pet-owners)