Asthma in Cats


Asthmatic cat in diabetic remission has corticosteroid problems

Question: Dr. Richards,

I have some questions for you , but first I need to give you some background information on my 11 year-old male cat, Fish.

Ever since he was about one year-old, he has had episodes of coughing, not necessarily related to physical exertion. I took him to vets and they said nothing was wrong with him. Eventually, one vet said that he might be asthmatic and gave him a steroid injection and then started him on oral steroids. We dosed him with the smallest amount necessary to control the coughing and that worked well. However, he eventually developed diabetes, I believe, as a direct result. I have read in the literature that steroid use can lead to the development of DM in those predisposed to it. We switched him from the steroid to oral theophylline and put him on a regimen of PZI with doses ranging from 1-7 units BID. We have a glucometer and do our own blood sugar checks at home, much better than the stress of the vet visit. Over the last two and a half years of insulin administration, we have kept him under control fairly well. Even so, we have experienced some diabetic complications. Fish developed oral infections and had most of his teeth extracted and also developed a bone infection in 5 digits on his paws. We noticed that several claws were growing in very thick, it reminded me of how fingernails look on an older person with poor circulation. This resulted in the amputation of the 5 digits (the bone that attaches the claw and the next one up). Fish has responded remarkably well to both of these procedures and appears much happier to not have the constant source of pain of the infected teeth and toes. After the recent procedures, we have continued on PZI BID until approximately one week ago. I noticed that Fish was quite lethargic in the midday, about the time the insulin reaches peak effect. We checked his glucose the next morning before insulin administration and found his blood sugar level to read 100. Therefore, we held that day's dose and checked again the next day. His level was 96. Since then, we have not given him any insulin and our next glucose check came in at 99.

I wanted to ask you two things. First, is it possible for a diabetic cat to self-regulate to the point of not requiring insulin injections? And, could they revert back to requiring insulin? Secondly, Fish's coughing has never been very well-controlled with theophylline and appears to be getting worse. We give him 25mg QD. Is there a better dose or a better medication without the side effects of steroids?

Thank you for a wonderful website and journal and for your attention to my questions.

Sincerely, Marcie

Answer: Marcie-

It is not unusual for cats to develop diabetes that requires insulin use and then to have a remission from the diabetes at a later time. It has usually been a few months in most of the cases we have had but I do remember one cat whose need for insulin stopped after about two years of treatment. It is a good idea to carefully monitor these cats because many will eventually need insulin again in the future, although it may be some time before the need surfaces again.

Asthmatic cats that have problems due to corticosteroid administration can be very difficult patients to help. We have been using cyproheptadine (Periactin Rx), at a dosage of 2mg every 12 hours in some of our asthmatic cat patients and it seems to help some of them, but not all of them. Cyproheptadine can cause very noticeable lethargy or depression the first week or so that it is used. Some cats become so inactive that their owners are reluctant to continue the medication. Most cats will adjust to the medication and seem to be normal after a couple of weeks, though.

Using a corticosteroid via an inhaler is supposed to avoid most of the systemic effects of the medications and it is possible to use an inhaler successfully. An anesthetic mask, pediatric chamber or just a toilet paper tube can be used to provide a temporary chamber for the inhaler to be sprayed into. The mask or tube is held over the cat's mouth and nose for 5 seconds after the pump of the inhaler to ensure that the cat inhales the medication. This isn't a solution that will work for everyone but it does help some of our cooperative patients a great deal.

For respiratory crises, we have started to dispense terbutaline to use at home. It is an injectable product and owners must be willing to make the injection but it can provide relief during severe asthma attacks. The dosage of is 0.01mg/kg of body weight injected subcutaneously. Many cats will respond well to this medication when they are having asthma attacks and it does give a treatment option that can be used at home for severe asthma attacks.

Dr. Padrid, writing in "Kirk's Current Veterinary Therapy XIII" discusses the use of cyclosporin in cats that are not responsive to other medications. The major drawbacks of this therapy are the need to monitor dosage levels through blood tests and the cost of the medication. He recommends starting at 10mg/kg every 12 hours and then adjusting the dosage based on blood tests for cyclosporin levels, testing weekly until a stable maintenance dosage is achieved.

There are some other medications that are being experimented with for asthma if one of the above suggestions doesn't work. I can research this more for you if necessary.

Mike Richards, DVM


Asthma in cats

Question: Hi Dr. Mike,

I am writing to you about my new cat which I adopted about 3 months ago. She is approx. 2.5 years old and a history of asthma. Her paperwork history is vague, with just treatments of Prednisone shots that she got approx. every month. My vet says these just masked the problem. Apparently she never had X-rays to try to see what cause could be. He is currently trying to get to the cause of her symptoms by eliminating possible causes, environmental, diet but it is hard to pin-point.

Her symptoms seem mild, just appear to be a stuffy nose to me (no attacks or anything). Snorty sounds occasionally. No excretion - seems to be way inside. No runny eyes, they are clear. Acts content & happy, eats well. She was on Hill's Id for a while because she had constipation problems but that has cleared & is on Nutro now with good results. Before she came to me who knows what she ate. Twice she seemed to get uncomfortable with her breathing & I caught her doing a few small open mouth breaths, that is when I brought her to the vet & he prescribed her Clavamox & Prednisone tabs to clear up congestion with good results. (He heard raspiness in her lungs at this point). He said good thing I brought her in but I almost didn't realize how bad she got.

So here we are again. I brought her back after 2nd round of Antibiotics & Prednisone and so far so good. Just a little stuffy sounding and vet said to wait to see how she does again. I am getting tired of bringing her in & not knowing cause. I agree with vet that it is good to try to get to cause of symptoms. My questions are could it just be a condition & maybe just get her on a decongestant at some point?. As far as environmental she is now in a condo with central/warm air, I have a humidifier (at vets sugg.) & she does not (will not) go outside. My feeling is diet is not a factor because she has symptoms no matter the food I give her. Maybe an upper respiratory thing? Any thoughts would be appreciated. Is Prednisone "bad" in the long run for cats as I've heard? Please advise...

Thanks, Kathy

Answer: Kathy-

The usual signs of asthma in cats include episodes of difficulty breathing that often occur suddenly, wheezing, decreased ability to exercise and coughing. This is a disease of the lower airways, so snuffling and congestion of the upper airways is not a typical sign. However, the episodes of open mouthed breathing that you saw are a sign of asthma, so it is possible that there are two conditions --- or that the upper airway problem caused enough difficulty with nasal breathing that your cat had to resort to open mouth breathing and asthma is not present.

There is no really good way to definitively diagnose asthma. There are changes on X-rays caused by visible thickening of the airways which can help in making a diagnosis and if a tracheal wash is done, high numbers of eosinophils are indicative of asthma ( but can occur in normal cats, too).

Upper airway disease is really common in cats, mostly due to recurrent attacks of herpes virus or damage to upper airway defenses from severe herpes virus infections as a kitten. Since you don't know much about the history of your cat, it would be hard to tell for sure which of these problems was more likely, if herpes virus is the problem. Administration of corticosteroids can alleviate the symptoms of this problem, even though they don't do anything to treat the underlying cause. Antibiotics are often helpful in upper airway disease because secondary bacterial infections are often present. Antibiotics are less helpful in asthma.

Long term use of prednisone in cats can cause problems, including an increase in the incidence of diabetes, secondary infections, behavioral changes and increased drinking and urinating. If possible, it is better to use inhaled versions of corticosteroids, which have fewer secondary side effects. There is a good article on asthma and use of inhaled medications in the November 2000 issue of The Clinics of North America by Philip Padrid, DVM, RN.

Your vet's plan to restart the diagnostic process and to work towards a definite diagnosis is a good one. It may take several efforts to find the right direction to go in --- whether to worry about upper airway disease, lower airway disease, general allergies, etc. Just keep working with your vet until you find a clear direction to go in. Unfortunately, the two most likely conditions, based solely on their incidence in cats, are herpes virus and asthma --- and both are chronic problems that will require maintenance care. But at least if you know what you are dealing with you can probably find some things you can do at home to minimize visits to your vet.

Hope this helps some.

Mike Richards, DVM


Feline Asthma

Question: Dear Dr. Richards,

Due to the fact that I have been trying to find accurate, up-to-date into on Feline Asthma on the internet & have found it to be a real chore, I was thrilled to find your site with its accurate info. & possibilities for new treatment modalities i.e. Iain's suggestions-see Asthma in Cats. Though I feel I have a good, caring vet, asthma isn't a high priority for her as there aren't many cases. Since I'm a nurse, I feel anything I can do to "source" new info. for her can be beneficial for both of us. If you have any good sites on current studies or recent info. on your vet. continuing education concerning asthma (feline), I'd be most appreciative in receiving those. Keep up the high quality of your site; many of us value it!Sincerely, L. S. G.

Answer: L. S. G.

I am not sure if this is on our site, or not. Dr. Phillip Padrid wrote an article in a Capsule Report a couple of years ago advocating the use of cyproheptadine (Periactin Rx) for asthma. He was using 2mg per cat given twice a day. I have not seen other literature references to this but it is probably pretty safe since Periactin is used a lot as an appetite stimulant in cats.

At a continuing education seminar that I attended the speaker said that a lot of cases of suspected asthma may be heartworm disease. Cats apparently react very strongly to the early stages of heartworm disease and can arrest or suppress the growth of the heartworms but develop severe respiratory disease in the effort, in some cases. This might be worth considering. But again, there are no other references that I am aware of supporting this theory.

We have had a couple of cases where we suspected asthma where we were able to find lungworm eggs in stool samples (they are not always present when this disease is affecting a cat). Both cats responded well to the administration of ivermectin. There have been some case reports of ivermectin reactions in cats being treated for ear mites, including some reported deaths, so it is important to be reasonably sure that lungworms are a potential problem before using this treatment. I am not sure if there are other treatments. Our two patients did fine and the coughing cleared up quickly after treatment.

We see enough cases where we do not find any other discernible cause that I feel that asthma by itself is not especially uncommon in cats. We have had the best luck treating with corticosteroids like prednisone, so far.

Veterinary Medicine magazine had a review article on feline asthma in September of 1990 that had some good information on diagnosis of this condition. If your vet subscribes to this journal, and saves it, he or she might still have this issue.

Recently, the use of antibiotics like azithromycin (Zithromax, Rx), which seem to work well against chronic upper respiratory bacterial infections, has been helpful in our practice in clearing up a couple of chronic sneezing/coughing kitties. It has definitely not been the answer for all cats but it would be worth considering if the response to prednisone isn't sufficient.

Hope this helps some.

Mike Richards, DVM


Feline Asthma in Tonkinese

Question: I came across your pages on feline asthma through a Web search. You might be interested in my experience.

I've got a 13 year old Tonkinese who has been diagnosed with asthma (largely based on no other positive diagnosis and good response to prednisone). Since I was concerned at the long term effects of systemic steroid treatment (I have already had one diabetic cat, through acromegaly of all things), I persuaded my vet to prescribe a Becotide 50 inhaler (50 ug beclomethasone per "puff"). Also, the prednisone wasn't very effective at the low doses which would have been "safe" for long term oral treatment.

Each puff is delivered into a 500 ml plastic bottle held over the cat's muzzle (muzzle sized hole at one end, and smaller inhaler nozzle hole at the other end). The bottle is held over his muzzle for about 90 seconds. Needless to say, this treatment was only considered 'cause the cat is very easy to handle and is not distressed by the process.

When his asthma is bad I give him 1 puff morning and night, sometimes 2 in the morning and 1 at night. This treatment is extremely effective, being almost as effective as the oral prednisone but without the systemic risks.

For treatment of the occasional acute attack my vet proposed Boehringer Ingelheim Ventipulmin Syrup (clenbuterol hydrochloride 25 ug/ml), 0.2 - 0.4 ml BID max dosage. This certainly seems to help his acute attacks, but is only used perhaps once or twice a week.

This overall regime has been used for about 14 months, and the cat is in excellent health.

NB - while not a vet, I have an honours degree in Physiology and Biochemistry, and I'm lucky to have a vet who is happy to involve me in the treatment decisions.


Answer: Iain-

We have used the inhalers for dogs with allergic bronchitis but have never tried this in a cat. Your method of administration is interesting. One of the best things about providing information online is learning new ideas from people who write to us. It is always good to have alternative suggestions for difficult situations such as asthma in cats.

Mike Richards, DVM

Feline Asthma

Dear Dr Richards,

Firstly I want to congratulate you on your excellent site, I am no computer buff, but I am interested in Internet through my youngest Son, Johny (13) who really loves internet /computer. He helped design my web site, hopefully be ready sometime this month. I am currently rather busy with relocation of my Vet Clinic. My Clinic is situated next door to the University of Western Australia Campus, in Perth, Western Australia. Although the Clinic was started 21 years ago it is still a very small Clinic. We have moved to a new location at the Highway just 600 metres from our original location. This move should have been done fifteen years ago. But better late than never.

The reason why I want to write to you is about Cat Asthma. As I mentioned, being next to a University where Medical School is available, I have a lot of Medical Practitioners as Clients or Medical Research Scientists. If I remember correctly, I was once told by a Research Professor of Asthma/ Respiratory System, that he uses a lot of Cats for his research because Cats DO NOT suffer ASTHMA. So , have you heard about this? If this is so, than your and many other Vets statements on Cats asthma can be 'unfortunate'.

I will ask this Client again when I see him, he also owns a Vineyard down South of Western Australia. May be the wine?

Anyway, since he told me about it 10 years ago I never mentioned or claim 'an asthma' attack again in Cats. My clinic is about 60 % Cats practice. But as I said it is a small clinic.

Best regards, Sudjar

Dear Sudjar,

Thank you for you kind assessment of our site. When I was in veterinary school there was a lot of argument over whether cats could have allergies since they did not seem to have a functional IgE system. There still seems to be some controversy over this but I think it is generally recognized now that cats do have allergic disorders. But that line of logic may have also led to the conclusion that asthma did not exist in cats. According to recent work by Drs. Dye and McKeirnan, published in the Journal of Veterinary Internal Medicine (10:385, 1996) and repeated in Dr. Morgan's book "Handbook of Small Animal Practice, 3rd. edition) there is demonstratable hyperactive airway disease in cats, which fits the definition of asthma. Other supporting evidence has been published previously, based on things such as radiographic interpretation and arterial blood gas analysis in affected cats.

One other problem I have struggled with in the past over these sorts of issues is the discrepancy that appears to exist between the way veterinarians use a descriptive term such as asthma or actinic keratitis and the way that human physicians define the terms. I think that sometimes it would be a lot better if we kept in closer communication with our physician counterparts!

Hope this helps to clear up the use of the asthma description. If you don't have it, Dr. Morgan's book is a very valuable resource and worth considering adding to any practice library.

Sorry for the long delay in replying to you.


Mike Richards, DVM


Q: Our Cat, Shadow, is under a vet's care. She sufferes from athsma, and gets "steroid" shots on a regular basis. We question what effect this is having on her overall health. She is 12 years old, and is in good health and physical condition.

She has been receiving these shots for about six years, and gets one about every three to four months. At the onset she received a shot about every six to eight months, but the frequency has obviously increased. We have been cautioned about her getting them too frequently, but have been unable to get more specific information. We then let her go for as much as another month after she develops her coughing and wheezing, before taking her in for another shot. Besides shots, we have also tried an oral medication, which did not seem to provide any relief whatsoever.

Please tell us as much as you know, since we are considering euthanasia, as we don't want her to suffer a worsening condition.

A: Asthma is fairly common in cats. Recently we have seen two cases that we thought were asthma based on clinical signs and X-rays that turned out to be

1) a case of heartworm disease and

2) a case of lungworm infestation. We discovered the lungworm problem completely by accident on a fecal examination for another problem. We check for heartworms frequently here due to our location near the Chesapeake Bay.

Asthma usually responds well to cortisone injections. Cats are much more resistant to the side effects of corticosteroids than dogs and humans. We have used cortisone injections as often as once every 3 to 4 weeks for several years in a number of cats without significant side effects. We have seen one or two cats that we think may have developed diabetes in part due to long term corticosteroid use.

When euthanasia is the alternative, I see no reason at all to worry over possible long term side effects of corticosteroids. In most cases, you won't see problems and in the cats in which diabetes or other complications do occur euthanasia at a later date seems a lot better than euthanasia sooner --- at least to me!

If you can maintain a schedule of using long acting cortisone injections at intervals of greater than one injection per month, I doubt you will see serious side effects, based on our experience using these injections in a cat. It is always worth reviewing the history and considering a re-evaluation of the problem in any chronic disease when the treatment seems less effective than it has in the past. Sometimes, the progression of a disease will point to another problem. You might want to talk to your vet about rechecking Shadow, just to put everyone's mind at ease about the diagnosis and long term treatment.

Mike Richards, DVM

Helping Asthma

Q: Dear Dr. Richards, I recently read about studies detailing the positive effects of using a negative ion charger around people with asthma. Do you think that a negative ion charger would be of help with feline asthma? My cat (7 y.o.) was on steroids for his asthma and developed diabetes from the steroids. I am hesitant to use any steroids at all to help his asthma and am seeking alternative medical treatments that will not interfere with his insulin needs. Currently, I give him 1/4 tab of Theo-Dur when his coughing begins, but I do not administer the medication on a regular basis. We have also bought an air purifier in the hopes of alleviating some of his allergic symptoms and we have all windows closed to prevent allergens from entering the house. Any advice you may be able to offer regarding the negative ion charger or any other treatments would be greatly appreciated. Thank you in advance for your time, Monica

A: Monica- I have not seen any research on the use of negative ionizers for cats with asthma but these fall in the "unlikely to hurt" category so I can't see any reason not to try one if you want to.

Other antihistamines may be helpful if theophylline (TheoDur Rx) doesn't work well enough. There are a lot of possible choices in antihistamines and sometimes it just takes some experimentation to see which one will work best.

Mike Richards, DVM

Last edited 09/23/02


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...