Dear Dr. Dog: My dog coughs a lot but seems fine otherwise. The vet says he has chronic bronchitis and that it might be from an allergy. She says he’ll probably always need medication for this. Why can’t this be cured like when people get bronchitis?
Chronic bronchitis and allergic bronchitis are basically the same thing – chronic means it’s been going on a long time and isn’t really changing very quickly, and allergic means it’s due to some kind of environmental allergy, like pollen, dust mites, molds, etc.
Canine bronchitis is usually due to some degree of allergy in the first place. Then, once it’s been going on long enough and becomes chronic, there can be permanent damage to the airways, leading to a reduced ability of the lungs to get rid of mucus and dust on their own, so a dog has to actively cough them up.
At that point, even if the allergy goes away completely, the dog may always have lungs that accumulate too much mucus. It can be worse during different seasons of the year, when there are more allergens or other contaminants (like smoke) in the air, and then better other times of year – even though the coughing may always be present to some degree.
Generally, a chest x-ray is taken to arrive at this diagnosis, although the only way to know for sure if an allergy is still contributing to the problem is to perform a bronchoscopic exam. For this procedure, a dog is lightly anesthetized and a flexible scope is passed down the trachea deep into the lungs, where a sample of mucus is obtained.
Dogs with suspected chronic bronchitis are usually treated with antibiotics to take care of any infection that might also be present, and then something is prescribed for allergies and inflammation in the lungs. Prednisone is a type of cortisone that usually works well to reduce the inflammation of the airways that results from active allergies – and also helps reduce mucus accumulation in the lungs, even if allergies are no longer part of the problem.
Unfortunately, full doses of prednisone can cause various side effects. Another medication, Temaril-P, is a low dose of prednisone plus an antihistamine in the same tablet, which can be used without the troubling side effects of straight prednisone.
If a trial of antibiotics and allergy medication works well, but the coughing recurs whenever the allergy medication is discontinued, then it is likely – as your veterinarian suggested – that an allergy medication of some kind will be needed continually to minimize allergies and reduce inflammation in the lungs.
Allergy shots can be given to dogs just like people, but while this approach will reduce active allergies in most dogs, it will not reduce the residual inflammation that remains in the lungs as a result of prior damage from long-term allergies or irritation from environmental sources like dust and smoke.
I strongly encourage our clients not to smoke around their pets, as both chronic bronchitis in dogs and lung cancer in cats have been linked to second-hand smoke.
As with all chronic conditions that have failed to respond well to treatment, a second opinion is a good idea. There are a number of specialty practices in the Bay Area, as well as the Veterinary School at UC Davis, where respiratory specialists can examine your dog and add their expertise to the discussion of how to treat your pet.
This is important to consider, because unusual infections, heart disease, and other problems involving the larynx (voice box) and trachea — even lung cancer of different forms, some of which are treatable — can all cause coughing in dogs.
In 1989, Dr. Franklin Utchen and Dr. James DeLano co-founded Norris Canyon Veterinary Medical Center in San Ramon, which became Bishop Ranch Veterinary Center in 2000. His special interests are orthopedic and soft tissue surgery, internal medicine, emergency/critical care, and dentistry. He has one daughter in college and lives in San Ramon with his wife and other daughter, along with their two Cavalier King Charles Spaniels, Tori and Gus. Learn more at the Bishop Ranch website, webvets.com.
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