Atopica for Cats: Dosage, Safety & Side Effects

Dr. Chris Vanderhoof is a 2013 graduate of the Virginia-Maryland College of Veterinary Medicine (VMCVM) at Virginia Tech, where he also earned a Masters in Public Health. He completed a rotating internship with Red Bank Veterinary Hospital in New Jersey and now works as a general practitioner in the Washington D.C. area. Dr. Vanderhoof is also a copywriter specializing in the animal health field and founder of Paramount Animal Health Writing Solutions, which can be found at www.animalhealthcopyw. View more

Positive interaction between a cat and a veterinarian, demonstrating the importance of regular veterinary visits and fostering a trusting relationship to ensure the cat

Atopica for Cats is a very specific brand of the drug cyclosporine, which is FDA-approved for use in cats. In this article, you’ll learn what Atopica for Cats is, what it’s used for, side effects and drug interactions to be aware of, and some frequently asked questions.

Atopica For Cats Overview

Medication Type: Immunosuppressive Capsules, Liquid Prescription Required?: FDA Approved?: Yes, but only the liquid form is FDA-approved for cats Life Stage: 6 months of age or older and weighing at least 3lb Brand Names:

Atopica (FDA-approved), Neoral, Gengraf; Note: the brand Sandimmune is unmodified cyclosporine and is not equivalent with Atopica

Common Names: Cyclosporine (modified) Available Dosages: Capsules: 10mg, 25mg, 50mg, 100mg; Liquid: 100mg/ml in both 5ml and 17ml bottle sizes Expiration Range:

Atopica: Capsules are stable in a freezer for 28 days. Liquid: after opening, use contents of the 5ml bottle within 2 months. For the 17ml container, use within 11 weeks.

What Is Atopica for Cats?

Atopica is a brand name for the drug cyclosporine. Cyclosporine is a systemic immunosuppressive agent called a calcineurin inhibitor that is used to treat illnesses caused when a cat’s own immune system either directly attacks a certain body system, or becomes over-stimulated, leading to a more indirect but no less debilitating state of disease. These types of illnesses are called immune-mediated diseases.

Atopica for Cats is a very specific liquid solution form of cyclosporine that is FDA-approved to treat allergic dermatitis, a skin condition caused by the immune system’s response to allergens. Atopica may also be used for a variety of other immune-mediated diseases in an off-label manner, at a veterinarian’s discretion.

What Does Atopica Do for Cats?

Atopica for Cats is labeled for treating allergic dermatitis, also called atopic dermatitis, in cats. Commonly referred to as skin allergies, this syndrome can have several presentations, including generalized itchy skin and scratching, scabs, alopecia (hair loss), and red ulcerative lesions called eosinophilic plaques.

Cyclosporine acts directly on the part of the immune response called cell-mediated immunity. Essentially, this is the part of the immune system that does not involve antibody production, but instead the body’s direct production of T-cells to attack foreign targets like allergens.

There are other immune-mediated diseases a veterinarian may decide to use cyclosporine for in cats that don’t involve the skin. These can include diseases of blood cells like pure red cell aplasia and immune-mediated thrombocytopenia, as well as the gastrointestinal tract like inflammatory bowel disease, and the mouth as in stomatitis.

Side Effects of Atopica in Cats

Anytime we consider using a systemic immunosuppressant, we have to consider the benefits vs. the potential risks. There are several points we need to consider when starting cyclosporine.

Digestive Upset

When using cyclosporine in cats, it may be expected to see signs of digestive upset during the first month of therapy. According to the product label itself, about 35% of cats showed signs of vomiting, retching, or regurgitation. Weight loss was seen in about 20% of cats.

The good news is that these effects reportedly resolve after a couple weeks of continued therapy. Some other side effects like poor appetite, salivation, and lethargy are much less commonly reported.

Effects of Immune System Suppression

Image of a cat appearing unwell, with a subdued demeanor and lethargic posture, emphasizing the significance of recognizing changes in behavior and seeking appropriate veterinary attention for ailing pets.

If a cat carrying toxoplasmosis is put on an immunosuppressant medication like cyclosporine, the inactive stage of the organism can become active again, causing actual disease.

Because cyclosporine suppresses the immune system, its use must be considered very carefully in light of any other health concerns a kitty has. While it can cause problems on occasion, the immune system of course is very important to general health and it can keep certain diseases in check.

Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are two viruses we can commonly see in the cat world that can weaken a kitty’s immune system even as it tries to keep them in check.

Suppressing the immune system further with cyclosporine use can worsen viral disease, and make a kitty more susceptible to other viral and bacterial infections that a cat with a normal immune system would easily be able to fend off. For this reason, it may be recommended to have a cat tested or retested for FeLV and FIV prior to starting Atopica long-term.

Similarly, any kitty that may have a weaker immune system for other reasons, such as an elderly cat, may also see a much higher risk of secondary infections.

Toxoplasmosis is also important to mention, as some cats can be carriers and use of cyclosporine carries a risk of it causing disease.

Toxoplasma is a protozoal organism that cats can acquire either through hunting birds and rodents or through exposure to the cysts in the environment. Once infected, most cats will only shed the organism in the stool for one period of a few days.

Cats then develop immunity to the organism, driving it into an inactive stage within the body tissues. While inactive, it is thought the organism can remain present for several years, possibly for the life of a cat. Most cats with toxoplasmosis show no signs of disease.

If a cat carrying toxoplasmosis is put on an immunosuppressant medication like cyclosporine, the inactive stage of the organism can become active again, causing actual disease.

This can pose a risk not just to a kitty, but also to her human family as well. Toxoplasmosis is the disease pregnant women need to be aware of, as it can be transmitted to people as well as to an unborn child, and is the reason a pregnant woman should avoid any exposure to the litter box for the duration of pregnancy.

It is considered very rare, but a case of a cat developing disease from toxoplasmosis after starting Atopica has been reported. Testing a cat for exposure to toxoplasmosis is possible, and while not often deemed necessary, at least for indoor cats, may be suggested by your vet depending on the circumstances.

Cell-mediated immunity is a very important component of the body’s ability to fight off cancers. Although also rare, suppressing this ability with cyclosporine could increase the risk for the development of certain cancers. To be clear, cyclosporine doesn’t cause cancer, but can allow an existing, unknown cancer to develop more readily by reducing the body’s ability to suppress it. Cyclosporine should not be used in kitties currently under therapy for known or suspected cancer.

Interactions With Medications

Lastly, cyclosporine can have interactions with a number of other medications. It’s very important to make sure your vet is aware of any other medications your kitty is taking, to reduce the risk of any possible negative effects.

While not often indicated when treating skin disease, your veterinarian may recommend lab work monitoring for your kitty when treating other immune-mediated conditions.

If you are ever concerned that your kitty may have developed side effects while using cyclosporine or if you’re concerned an overdose may have occurred, make sure to immediately contact one or more of the following for advice:

Atopica for Cats Dosage

Cat receiving an injection from a veterinarian, highlighting the role of medical interventions in maintaining feline health and the expertise of veterinary professionals in administering necessary treatments.

The dosage of Atopica for Cats is 7mg per kg of body weight each day.

The labeled dose for Atopica for Cats is 7 milligrams per kilogram per day or 3.2 milligrams per pound per day, and should be continued for a minimum of 4-6 weeks to determine if it is being effective.

From there, your veterinarian will typically reduce the frequency of administration, which is called tapering, to the lowest frequency that still provides the most benefits. Some cats for example, may maintain well on dosing every other day or just a couple times a week. It is very important however to only adjust a medication dose or frequency under your veterinarian’s guidance.

While cyclosporine generally can come in a couple of different dosing forms, Atopica for Cats comes in only one specific formulation as a 100 mg/ml oral solution. Because cyclosporine can present a risk to humans handling it (which we’ll discuss in the next section), the dispensing system of the bottle and oral dosing syringe are designed specifically to minimize skin exposure to the liquid.

It’s important to assemble the dispensing system correctly, using the provided packaging insert, and instructions from your vet.

How to Properly Handle Cyclosporine Products?

Although a very beneficial medication, the immunosuppressive effects of cyclosporine necessitate very careful handling by human family members administering this drug to kitties.

The dosing assembly of the bottle and syringe for Atopica for Cats is designed specifically to limit exposure of the skin to the liquid medication, however using gloves is recommended for dosing, especially if giving it directly into a kitty’s mouth vs. mixing it with some food.

The manufacturer advises washing your hands after administration but recommends not washing or rinsing the oral dosing syringe after use, to limit exposure.

Gloves should certainly be worn when giving any other forms of cyclosporine too, like other liquid formations or capsules.

Modified vs. Unmodified Cyclosporine: What’s the Difference?

Image of an unwell cat, visibly displaying symptoms of illness such as lethargy and hunched posture, underscoring the importance of timely veterinary care when a cat

Your veterinarian will discuss the benefits and risks to Atopica’s use specifically for your kitty depending on other medications he may be on or other health concerns that may exist.

There are two general forms of cyclosporine that exist: modified and unmodified. Unmodified cyclosporine is kind of its original form, but this form is far less bioavailable and can’t be used as efficiently by the body.

The modified form is much more effective, especially in cats and dogs. It’s important to know this, because the dosing for unmodified forms of cyclosporine, like the brand Sandimmune, are not equivalent to modified forms like Atopica and Neoral.

This is especially important when looking into generic forms of cyclosporine as well as when a compounded formulation of cyclosporine may be needed.

Conclusion

Cyclosporine in the form of Atopica for Cats is a very beneficial medication. However, because it does suppress the immune system, there are many precautions that need to be taken and considered with its use.

Your veterinarian will discuss the benefits and risks to Atopica’s use specifically for your kitty depending on other medications he may be on or other health concerns that may exist.

Drug Dosing Disclaimer: We are only able to provide doses for medications that are FDA approved for use in cats and only as the label guidelines dictate. For medications that are used off-label we can only provide guidelines and safety information for use. Safe and appropriate dosing for off-label medications can only be determined by a primary care veterinarian.

We encourage you to work with your veterinarian to determine if a particular medication is appropriate for your cat. Changing or adjusting a dose for your cat on your own without consulting with a veterinarian can carry risk. We do not encourage use of medications prescribed for human use in pets without first consulting with a primary care veterinarian.

Frequently Asked Questions

How Long Can a Cat Stay on Atopica?

Given the nature of the types of diseases Atopica is used to treat, many cats will be on this medication for a very long time, sometimes for life. It is always the goal to taper Atopica’s dosing frequency down to the lowest effective dose, to minimize potential side effects and make it as safe as possible long-term.

While there are some cases where an immunosuppressive medication’s dosing and frequency may be tapered down enough that it can be discontinued, this should not be a common expectation.

In some cases, especially if side effects are seen, other medications or therapies may be considered.

Should Atopica Be Given with Food?

While cyclosporine should be given on an empty stomach in dogs, there is reportedly no difference in absorption of the medication in cats whether it’s given with or without food. However, it is recommended that whatever way is chosen, that this method of administration is kept consistent.

When giving with food, it is recommended to administer directly onto a small amount of canned or soft food to ensure that the dose is consumed.

What does Atopica do for cats?

Atopica is an immunosuppressive medication, meaning that it reduces the immune system’s impact on the rest of the body. More specifically, it affects cell-mediated production of T-cells, which is the part of the immune system not related to antibody production.

Atopica’s use can be important when the immune system is responsible for causing active disease by either over-reacting to a stimulus, as with allergic skin disease, or when targeting a specific body system or cell line as with the platelet disorder called immune-mediated thrombocytopenia or red blood cell disorder called pure red cell aplasia.

Atopica for Cats is labeled specifically to aid in the control of feline allergic dermatitis, but may be used off-label at the discretion of a veterinarian to treat other disorders caused by the immune system.

What are the Side Effects of Atopica in Cats?

The most common side effects are related to digestive upset, like vomiting and regurgitation. Most of these signs fortunately tend to clear up on their own beyond one month of continued use.

There can be other side effects less commonly seen. As an immunosuppressive medication, cyclosporine can increase the risk for certain diseases the immune system may be normally keeping at bay, including bacterial infections, viral infections, protozoal infections like toxoplasmosis, and cancers.

Cyclosporine can also have interactions with many other medications, so it’s very important to make sure your vet is aware of other medications your kitty takes before starting Atopica for Cats.

Help us do better! Was this article helpful and relevant? What can you say about this article?

I am completely satisfied, I found useful information and tips in this article

Article was somewhat helpful, but could be improved

Want to share more?

Thank You for the feedback! We work to make the world a better place for cats, and we're getting better for you.

About Dr. Chris Vanderhoof, DVM, MPH

Dr. Chris Vanderhoof is a 2013 graduate of the Virginia-Maryland College of Veterinary Medicine (VMCVM) at Virginia Tech, where he also earned a Masters in Public Health. He completed a rotating internship with Red Bank Veterinary Hospital in New Jersey and now works as a general practitioner in the Washington D.C. area. Dr. Vanderhoof is also a copywriter specializing in the animal health field and founder of Paramount Animal Health Writing Solutions, which can be found at www.animalhealthcopywriter.com. Dr. Vanderhoof lives in the Northern Virginia area with his family, including 3 cats.

Connect with Dr. Chris Vanderhoof, DVM, MPH: Get more Cat Health articles - straight to your inbox

Sign up and we’ll send you Cats.com articles about the all aspects of cat health to help you keep your fluffy treasure healthy.

More From Cat Medication

Cat with insulin bottle and syringe

home interior with brown indoor cat stepping out of closed kitty litter box in living room

High angle view of woman feeding with dry food her cat at home

Owner of the cat is treating with eye drop

Popular in the community

The image portrays a cat exploring the bathroom environment, with its attention directed towards the toilet and sink.

An adorable gray and white cat playfully nibbles on a person's feet, showcasing its playful and affectionate nature.

An image symbolizing the concept of healing and recovery. The image might show a cat in a relaxed pose, perhaps lying down with closed eyes, as if in a state of rest and recuperation.

JOIN THE FAMILY

14 thoughts on “Atopica for Cats: Dosage, Safety & Side Effects”

+ Add Comment

Leave a Reply Cancel reply

  1. Steph LJan 20, 2022 at 2:58 pm Is their something else I can give mg 16 lb cat with diabetes considering Atopica is out of stock everywhere? My cat is very sick and needs it. Can’t afford the price to compound the one place that sells it. I am a single parent of a diabetic cat, dog with congestive heart failure & a small child! PleAse help me find something to help him!

  1. Dr. Chris Vanderhoof, DVM, MPH Post author Jan 20, 2022 at 3:45 pm Hi Steph, Supply chain issues have been causing shortages of many different products in recent months, which ultimately is affecting care of pets that need them. I’m very sorry to hear you and your kitty have been affected. Cyclosporine (Atopica) is used to treat many different conditions in cats, so I may not be able to answer your question fully as I am not familiar with your kitty or the reason that he’s on Atopica. The steroid prednisolone often makes for a reasonable way of treating certain immune conditions and can be used in the short-term if a preferred long-term medication like cyclosporine becomes unavailable. Unfortunately though, as your kitty is a diabetic, use of prednisolone could complicate regulation and cause new problems, which is unfortunate. You may already be familiar with that problem from discussions with your vet, making prednisolone a not-so-great choice here. If this is a skin-related disease, like atopic dermatitis, Apoquel has been used successfully in cats for a few years and you could speak to your vet further about that if applicable. If this is a digestive condition, you could speak to your vet about the steroid budesonide, which has far less impact on the body as a whole, focusing mostly on the digestive tract, and would be less likely to interfere with diabetic regulation. We have articles on both Apoquel and Budesonide that you could read and see if they might apply to your cat’s situation and to help open a dialogue to speak further about options with your vet. Beyond my insight there, I couldn’t speak further on what else could be used, because it depends heavily on the medical condition. There are other immunosuppressive medications out there for other conditions that you could speak to your vet further about.

  1. Dr. Chris Vanderhoof, DVM, MPH Post author Sep 12, 2022 at 12:55 am Hi Sarah, Immune-mediated thrombocytopenia, which is the term for what it sounds like your kitty is being treated for, can have many underlying causes, and unfortunately, pinpointing that cause is very difficult and often never occurs. A blood disorder resulting from an autoimmune trigger may happen shortly after the trigger or it could be weeks or months later. Anything that stimulates the immune system could in theory lead to an inappropriate response by the immune system to attack normal cells in the body. However, to my knowledge, a general allergy to a plant is unlikely to lead to an autoimmune blood disorder. Any kind of inhaled pollen or other allergen is more likely to lead to asthma in cats and less commonly, atopic dermatitis or skin allergies. Of course, true lilies singularly pose a toxic risk to cats’ kidney function if they inhale the pollen or ingest any part of the plant, but to my knowledge, when this toxicity occurs, an autoimmune response is unlikely to occur, as this is not an allergic response but a toxicity. If it’s been two years and your kitty’s signs have been controlled with Atopica (and clearly it continues to be needed) a bone marrow disorder interfering with platelet production is most likely, as has probably been discussed. The recurrence of bruising sounds more like it might have been related to the tapering down of Atopica allowing the immune disorder to resurface. You could discuss a bone marrow biopsy with your vet, as sometimes you can get an answer in terms of an underlying cause, but given that Atopica controls your cat’s signs well and the results of a bone marrow biopsy likely wouldn’t change the treatment plan, it could be argued that an invasive test like that wouldn’t be in your cat’s best interest.

  1. Dr. Chris Vanderhoof, DVM, MPH Post author Dec 22, 2022 at 4:47 pm Hi Carolina, thanks for the question. Generally, your dose will aline with the very bottom of the plastic piece or rubber end to the plunger in the syringe. It is important for accurate dosing to remove any air you’ve got trapped in there. To do this after pulling up the volume of medication, turn the syringe so that the tip is facing up towards the ceiling. The air bubble may move its way towards the tip on its own. If it doesn’t, give it a little flick with your finger to encourage any air to float towards the tip of the syringe opening. You can also pull back a little bit on the plunger in that position to help make sure all medication collects at the bottom. When the air is all at the tip, you can push it out carefully, being sure not to expel any medication. You can then see exactly how much liquid dose you have in there without the air in the way. I hope that helps.

Dr. Chris Vanderhoof, DVM, MPH Post author Sep 4, 2024 at 2:29 pm Thanks for sharing your tips Carolina. I’m not surprised that you are unable to find any syringes to fit the dispensing hole on the Atopica bottle. The syringe that comes with the bottle is designed to function as a unit with it to dispense the medication. The syringe that comes with the medication is not a generic one and is designed specifically for Atopica dispensing. While you can remove the dispensing hole and use another syringe as you describe, it may lead to less accurate dosing in some cases. If you don’t use the inverting method the way the bottle and syringe are designed, and instead dip the syringe into the bottle, you may get medication on the syringe itself, inadvertently leading to waste, so you’d have to be careful. Using a generic syringe, you also must make sure to carefully calculate the volume. The Atopica syringe makes it more user friendly as you can pull up the right volume based on your cat’s weight. With a generic syringe, you need to double check to make sure the volume is correct. The labeled dose for cats for Atopica is 3.2mg/lb or 7mg/kg. As an example for a 10lb cat, that makes about 32mg. The solution concentration is 100mg/ml, so you must divide the 32mg by 100 to get your actual volume of about 0.32ml. It may be difficult to get that exact volume with some generic syringes. I can’t deny that using a syringe that eliminates hub waste may save some on volume if you do it carefully and you may get an extra dose every several days depending on a cat’s size, but it may be too complicated for some folks vs. using the bottle/syringe unit as designed.

  1. Dr. Chris Vanderhoof, DVM, MPH Post author Nov 1, 2023 at 6:11 pm Hi Patty, Generally I’d say you should be okay and hopefully you have not seen any signs of concern as long as your cat has been tolerating the Atopica okay in general. According to Plumb’s Veterinary Drug Manual, cats given up to 40mg/kg as a single overdose of cyclosporine showed no signs of ill effects. If a dose this high is given over weeks or months, intensified side effects may be seen. But if you’re giving the labeled dose of 7mg/kg to your cat and the double dose ended up being 14mg/kg, you can see that’s still well under that 40mg/kg threshold. Even with that happening two days in a row it would not appear to be a major concern. As a tip though for anyone, this blog should be for non-urgent questions as a response may take up to 2-3 days. If something urgent or concerning occurs, make sure to direct questions to your veterinarian or a local emergency hospital. For medication overdose or toxicity concerns, you can also contact the ASPCA Poison Control Center or the Pet Poison Helpline.

  1. Dr. Chris Vanderhoof, DVM, MPH Post author Nov 16, 2023 at 2:09 pm Hi Mary, I think that ultimately, the choice is yours and that it’s important to consider the costs and benefits. I always suggest to look at whether the risk of any medication or procedure may outweigh the benefits. On the flip side I also think it’s important to utilize a medication if there is a significant disease present that needs treatment. Side effects are not guaranteed, only possible, and sometimes they can be mitigated with medication dosage adjustments. If these are eosinophilic plaques, atopica likely would help with them but as a broad immunosuppressive medication, there are potential side effects to consider and a need for extra labwork monitoring. Your vet is trying to do what is most appropriate medically, but if you don’t feel that the areas of concern are uncomfortable or causing your cat distress, it is reasonable to have that discussion about monitoring and waiting on Atopica. It’s possible a dietary change may help, though often the underlying cause of eosinophilic lesions is not fully clear. It is possible for them to worsen and become uncomfortable, so close monitoring at least would be prudent.

  1. Dr. Chris Vanderhoof, DVM, MPH Post author Jan 31, 2024 at 2:40 am Hi Marlene,
    I wouldn’t see an issue with keeping your dose in the syringe overnight or in putting the dose into a gel capsule. But the manufacturer indicates not to refrigerate the liquid Atopica and that it should be stored at room temperature (15-25C or 59-77F). I think therefore that freezing the liquid would not be appropriate. If there might be concern that refrigerating may affect the medication, freezing and thawing certainly would.