Coughing in Cats

Coughing in Cats

Coughing - asthma or bronchitis

Question: Dr. Mike,

Thanks for your advice on feline asthma--it is one of the few sources I have found that addresses this condition in any detail. My 11 year old indoor cat, Cleo, was diagnosed with chronic low grade bronchitis/asthma about 2 years ago. She has been tested for heartworms (negative) and has received regular x-rays which appear to confirm this diagnosis of bronchitis. At first she responded well to prednisone, but recently she stopped responding to the doses that had been working before (2.5 mg every day or 5 mg every other day). She tends to have coughing episodes every morning at around 5 or 6 am, which last about 1 minute, with rare coughing at other times. Between episodes she seems fine. She eats well, and her activity is normal for an 11 year old cat.

The vet cautioned against overtreating the condition with prednisone--although she never coughs while we are at the vet (of course), he said that if she had asthma there would be some evidence of problems with her breathing in the hours after an attack (i.e., in the late morning after a 6 am attack). Because there was none, he said the condition is chronic bronchitis.

We tried to identify allergens/irritants, but have had little luck. I already have HEPA filters both up and downstairs in my apartment. The only thing I can think of is pollen, which is really bad here in Washington, DC right now.

About a week ago, the vet agreed that it would make sense to see whether Cleo's coughing became any worse without the predisone. I stopped giving it to her, and although the coughing continues, it has not worsened.

Here is my question: Is it better (1) to allow Cleo to cough on a regular basis, or (2) to give her enough prednisone to keep the coughing down? I am afraid that I will come home one day and find her dead, or that she will develop emphysema, if untreated. However, I am also worried about the long term impact of predisone treatment. She has already been on low doses for 2 years, and she is almost 12 years old. Thanks so much for any advise you can give me--

Sincerely, Kristi

Answer: Kristi-

I find it hard to differentiate between chronic bronchitis and asthma. There are some things that help in telling them apart, though.

Asthma does often cause coughing as the primary clinical sign. However, it is true that acute respiratory distress is a stronger feature of asthma and that there are often harsh breathing sounds with asthma. Usually, asthma will respond to bronchodilators, either injectable (terbutaline) or inhaled (albuterol) during the acute attacks.

Chronic bronchitis also causes coughing as the primary clinical sign in many cats. Instead of acute attacks of respiratory distress the cat usually shows signs like tiring easily or increased respiratory rate during normal activities, including sleeping. Chronic bronchitis will not usually respond to bronchodilators.

The major difference between treatment for chronic bronchitis and asthma is that you have the option of using bronchodilators, if effective, for asthma but these will not usually help with allergic bronchitis conditions. Both disorders will usually respond to corticosteroids. These may be given orally or by using inhalers. If it is possible to use inhalers they are a better choice because there is much less systemic effect from inhalers.

When asthma is not causing too much difficulty, it is probably acceptable to treat it with bronchodilators only, especially if it is possible to use inhalant bronchodilators. These can be used only when there is an asthmatic episode in some cats. If the asthma is more severe it may be necessary to use corticosteroids, though. If inhaled corticosteroids are used the only one that I am aware of is Flovent (Rx), which comes in three strengths. It is usually necessary to use one of the two higher strengths in cats to get a beneficial effect. It is necessary to use a pediatric inhalation chamber, an anesthetic mask or some other "chamber" to allow the inhaler's medication to be inhaled by the cat. The chamber usually has to be held over the cat's nose and mouth for 5 to 10 seconds to ensure that the medication is inhaled. It can be helpful to keep injectable terbutaline at home, as well. I think that all of this information is covered in a recent Clinics of North America (September 2000?) and "Kirk's Current Veterinary Therapy XIII". Your vet may have one or both of these references. As far as I know, there are no controlled double blind studies to support the use of these medications for asthma in cats, so this information is anecdotal at this time.

Cats with chronic bronchitis respond better to corticosteroids and sometimes to antibiotics, if there is a secondary infection. Over the long term, corticosteroids have the most beneficial effect. Just like with asthma, it should be possible to lessen the long term effects of corticosteroid use by using inhaled corticosteroids like Fluvent, if that is possible.

Controlling coughing should make a difference, in theory, because coughing causes further inflammation of the bronchi and over time this could make the disease process worse. I am not sure that anyone has studied coughing cats that are not treated long term to see how much difference it makes not to control the coughing, though.

It seems logical to me that there will be more and more acceptance of inhaled corticosteroids over time for cats. The initial reaction of most vets is that it will be impossible to use inhalers in many patients and that the cost of the inhalers and the apparatus to make the work is therefore difficult to justify. Over time, if there is more success than failure using these treatments, the tide will probably turn towards their use. At this point, if you decide to try this approach, you will part of the initial experiment to see how useful these medications will turn out to be. Our experience, so far, is that the inhalers have not made any cats worse and have helped as far as we can tell, but that there are some cats who do notcooperate enough to make the use of the inhaler practical for their treatment. We have only treated four cats in this manner and only one of them refused to cooperate at all, so far.

If I had to choose between not treating for asthma and using low doses of prednisone on an every other day basis (if that does help), I would choose the low doses of prednisone in most cases. I am really hopeful that we will be able to control some of the asthma cases with alternatives such as medications delivered through inhalers, though.

I hope that this helps some. Your vet can get a lot of information on this subject from the two references above or from the online database of the Veterinary Information Network (

Mike Richards, DVM 5/22/2001


Question: Hi Dr. Mike:

I currently have 7 wonderful cats. One of them starting coughing about a year ago so I took her to the vet and he took x-rays. He said she had some fluid in her chest and asthma. So the vet started her on 20 mg. of Depomedrol. The coughing stopped but 2 months later it started again, so I brought her in for another shot and this time, she still kept coughing. I then found out that if I kept her on this drug long-term, she could possibly get diabetes and liver disease in the future. So I discontinued the shots. She still coughs once in a while, but it seems to have subsided. Now, 2 of my other cats are coughing and I'm beginning to think this is more than asthma. I feel that it might be some kind of contagious thing going around. The vet told me to give them Laxatone, but it is not working. Now, all 3 of them are coughing and the vet doesn't seem to know what it is. (Just for your info -- they were all tested for FELV, FIV, and FIP before I brought them home.) What do you think this could possibly be? Any info you can give me would be greatly appreciated. Thanks.

Sincerely, Janice

Answer: Janice -

Coughing occurs in cats due to asthma, heartworm disease, roundworm migration, lungworms, cardiomyopathy, from nasopharyngeal polyps, chronic bronchitis, bordetella infection, fungal infection and probably some other conditions that I can't come up with right now.

Some people have a really hard time differentiating retching from coughing in cats, so inflammatory bowel disease and other causes of retching type vomiting have to be considered, unless you are really certain this is coughing.

Assuming you are pretty sure this is coughing, the most common causes are probably asthma and heartworm disease. Neither one of these is contagious directly from cat to cat, but it isn't too unusual to have more than one cat in a household with asthma, especially if there is an environmental irritant like cigarette smoke. It is unusual to have more than one cat in a household with heartworm disease but it isn't impossible.

Bordetella bronchiseptica, a bacteria that causes tracheobronchitis in both dogs and cats, is possibly the most common contagious bacterial infection causing coughing in cats. Usually in adult cats this is a mild transient infection, clearing up without treatment in 2 to 3 weeks. However, it can cause more serious disease in some circumstances. This is the most likely contagious illness among the illnesses that cause coughing. Hopefully, if it was the problem the cats are OK again, now.

Parasitic causes of coughing include lungworms, roundworms,and toxoplasmosis. Roundworm migration and lungworms can both be hard to detect, so sometimes we just deworm with wide sprectum dewormer to see it helps. We have used fendebendazole (Pancur Rx) and ivermectin (Ivomec 1% Rx) for this purpose. Heartworms are a problem in our area and we do see some cats coughing due to this parasite. We have not seen this in more than one cat in a household, yet, that I can remember, though.

I have a hard time being certain that asthma is present based on X-rays. If your vet is not sure of the diagnosis having a radiologist examine the films can be helpful.

If you live in an area where fungal diseases are common (mostly the Southwest), it may be necessary to rule out these diseases, as well. they are not common where we live and I am not sure how often coughing is a problem with them, it is just always listed as a possible clinical sign.

Cortisones are the most consistently effective medications for asthma. There is more and more interest among vets in using the inhalers to deliver cortisones since there is less systemic problem with corticosteroids delivered through inhalers. This might allow effective treatment of the asthma with very little risk of complications such as diabetes or liver damage. Another alternative that works for some cats is cyproheptadine administration (Periactin Rx).

Mike Richards, DVM 5/18/2001

Coughing in cats

Question: Dear Dr. Richard:

I saw my cat waking up coughing in the middle of the sleep and coughing soon after waking up from the sleep for a couple times. It looks like he is choking and disappears after a few moments. What could be wrong with my cat? Is it serious? He likes to eat cat litter and can it cause the coughing? Is cat litter dangerous for cats to eat? He always get stained with waste oil from rubbing (playing underneath) the car and he licks it from his coat and face. Is this causing the coughing? What should I do? I am very worried.


Answer: Thandar-

The most common causes of coughing in cats are probably asthma, chronic bronchitis and heartworm disease. Bordetella bronchiseptica infection can also cause coughing but is not too likely in a solitary cat or in house with two or three cats. It usually causes problems in shelters, catteries and other places with lots of cats. Vomiting or retching can be hard to distinguish from coughing in cats, so inflammatory bowel disease and other causes of chronic vomiting have to be considered, too.

It would probably be a good idea to find out from your vet how likely heartworm disease is in your area and to consider testing for this if it seems appropriate to do that.

Petroleum products may cause coughing or gastrointestinal irritation, although we don't see this too often.

Cat litter can definitely cause upper respiratory irritation and may incite asthma attacks in susceptible cats. There are no confirmed cases of problems from eating cat litter than I can find in the literature, although there are persistent rumors of problems with scoopable litters. Dogs eat a lot more cat litter than cats do, though -- and I only know of one confirmed case of an intestinal obstruction in a dog from eating cat litter and it ate nearly the entire contents of a litter pan! Using a litter that produces little or no dust reduces the problems with respiratory disease in cats prone to chronic bronchitis or asthma.

Your vet should be able to help you sort through these possibilities and find the cause of the coughing in your cat.

Mike Richards, DVM 7/9/2000

Coughing and sneezing

Question: Dear Dr. Mike, First, I would like to tell you how much I enjoy your site and the Vetinfo digest. I am a new subscriber. I have a big problem that I hope you will be able to help me with. In January 0f 2000 I adopted a young kitten (Approx) 5 to 6 months old from my vet. It had been dropped off at her clinic in really bad shape. Her first inclination was to put it to sleep, but being who she is she decided to try to save him.

He had a really bad upper respiratory infection, was full of worms and starving, she had him in her clinic for about 3 months before I adopted him. After I got him home he continued to Sneeze and cough a lot. When he sneezes he discharges a lot of mucus from his nose and the cough sounds like a croupy cough. The Vet put him back on antibiotics )Orbax 22.7 mg) for 10 days along with Gentocin Eye Drops to try and clear his nose he also has had booster shots for FVPCP twice to see it that would help.He has recently had a depo medrol injection which seems to have helped.I recently had a fecal test done and he had roundworms for which he has been treated for and the cough seems much better.He is now on Baytril 22.7 mg at 1/2 tablet per day which is keeping the sneezing controlled but if we take him off the Baytril he starts sneezing again.His eyes have always been clear (no running) He is happy, active and eats good.

I also have another cat 2 years old and she has been fine from January till now but the last week she has been sneezing and coughing a bit. She is not on any medication and I am not sure if I should have her on something or let her own immune system fit it.

I have scoured the Internet trying to find some answers as to what can be the matter but have been unable to find anything that matches his symptoms (Sneezing and coughing together). I hope you might have some other suggestions as to what could be his problem and any other treatments I could try. I apologize for the length of this letter and I haven't taken up to much of your time but I am at my wits end with this problem

Thanking you in Advance, Jean

Answer: Jean-

When coughing and sneezing occur together there is a chance of a herpes virus infection with secondary bacterial infection and of bordetella vaccine as a sole pathogen or a secondary infection.

There are a couple of reports of bordetella being resistant to enrofloxacin (Baytril Rx). Doxycycline and sulfamethoprim-trimethoprim combinations are both supposed to work well for bordetella, so it might be worth changing to one of these to see if they can clear up the infection and keep it away. Tetracyclines (doxycycline is in this class) sometimes cause discoloration of tooth enamel when used in kittens but this is not thought to be harmful to the teeth. Sulfa-trimethoprim combinations cause some cats to salivate really excessively -- enough that many of our clients are very worried by it even though we tell them it might happen. Still, even with the side effects these are reported to be the best antibiotics for bordetella and will work for most other upper respiratory bacteria, as well.

L-lysine can help control herpes virus replication, which will sometimes help to reduce the severity of chronic upper respiratory symptoms, as well.

If your vet agrees that changing antibiotics might be helpful but it doesn' t work out, you may have to consider further diagnostic testing. Possible testing procedures include culture and sensitivity testing, X-rays, MRI and endoscopic examination of the nasal passages. It is hard to decide which is the best approach, so your vet will have to help you decide which is the best course of action.

Hope this helps some.

Mike Richards, DVM 5/27/2000


Q: My question concerns my cat Mikko. He has had an almost two month long period of coughing. Not constantly, but maybe once or twice a day. The coughing lasts from a few seconds to several minutes. We work in San Diego three days a week, so we have not constantly been able to keep an eye on him. We trust our vet, who is a university graduate, but he is perplexed. First he received antibiotics. The latest prescription was for BISOLVON ESPECTORANT and PISATRINA. It seemed to have helped a little, but Mikko is still coughing, and we are at a loss of what to do next. We sincerely hope you might have some suggestions on how to treat the cat. My husband is hopeless when it comes to giving shots to a grumpy cat, but will do whatever is needed to help our friend.

A: There are not very many causes of coughing in cats. The most common causes are heartworms, asthma, chronic tracheobronchitis, cardiomyopathy and lungworms. Depending on where you live, heartworms and lungworms may be pretty rare. Heartworms are carried by mosquitoes and some areas simply don't have a problem. Lungworms are more common the farther south you are. There is often a heart murmur if cardiomyopathy is present, so listening for this on a physical exam is a good first step in making a diagnosis when coughing is a problem. If there is no murmur we test for heartworms. We usually take X-rays whether the test is positive or negative -- to assess the damage if the test is positive and try to help confirm an infection and to look for signs of asthma if it is negative. Sometimes we just deworm for lungworms since they are hard to find on a fecal exam or tracheal wash and then if we are still confused we refer the cats to a specialist who can do cardiac ultrasound exams. Heartworms and asthma both respond reasonably well to corticosteroids but heartworm is still dangerous because this only controls the symptoms and there is not a good treatment for cats. Lungworms are treatable with medications. Cardiomyopathy responds variably to medications but can usually be managed. Hopefully your vet has already started working through these problems with you.

Mike Richards, DVM 4/6/99

Chronic Coughing

Q: Dear Dr. Mike, Esmeralda is eleven years old. She has had a chronic cough for the last few months which has become more persistent in the last few weeks. The vet says it is caused either by fluid on the lungs or a mass in thelung. She was given an antibiotic injection and pills to take at home. It has been over a week with no real change in the cough. About ten years ago a vet saved her from a coyote attack. He said the attack destroyed most of one lung but she could live a normal life albeit a little slower than most cats. She became a totally indoor cat after that. X-rays were taken on her last visit to the vet and showed shadows. Could these be scar tissue from that coyote attack? He didn't seem to think so, but he wasn't the vet who treated her for that. What is her prognosis if it's a pnemonia type disease? A lung mass? Thanks very much

A: It is pretty important to figure out what the exact cause of the coughing is, if that is possible. Chronic coughing can be caused by asthma, chronic bronchitis, heartworms, lungworms and cancer. These are probably the most common causes of chronic coughing but there are other diseases that can lead to coughing, as well. The treatment and the prognosis vary a lot depending on what the problem actually is.

Even though it is somewhat expensive to retake the X-rays, that may be indicated. Many times, things which do not show up very well on initial X-rays will be plainly visible in a week or a month or several months. This is especially true of chest tumors. We send a fair number of our X-rays to radiologists for review. They are simply better at reading the radiographs than I am. You and your vet might consider this option if the X-rays still seem to be inconclusive when retaken.

Please let your vet know that the coughing is continuing and work with him to get a diagnosis so that a treatment plan can be worked out.

Good luck! Mike Richards, DVM

Last edited 12/05/02


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...