How Asthma Affects Dogs
Asthma is basically a term for difficulty breathing (called “dyspnea”). It usually includes wheezing and shortness of breath due to spasms and constriction of the large upper airways (the trachea and bronchi). Dogs, like people, can develop asthma, although in dogs the disorder typically is referred to as allergic bronchitis. In dogs, this condition is almost always caused by an allergic reaction to something in the environment, which in turn causes an inflammatory response in the upper airways. Most of the time, the allergen is something that the dog inhales. Long-standing allergic bronchitis can damage the tissues lining the respiratory tract, causing the more permanent changes associated with chronic bronchitis.
The symptoms of so-called “asthma attacks” can vary widely from occasional breathing problems to severe dyspnea that approaches suffocation. By the time the condition is this severe, it usually has become chronic and irreversible. In very grave cases, the dog may resort to open-mouth breathing, and its gums and other mucous membranes may turn a purplish-blue from oxygen deprivation. When the consequences of asthma become this severe, the dog needs immediate emergency veterinary care to survive.
Symptoms of Allergic Bronchitis
Canine allergic bronchitis tends to affect young to middle-aged dogs, although older animals occasionally are affected as well. The hallmark of allergic bronchitis is a chronic, dry hacking cough, which can come on slowly or suddenly. Other common signs include:
- Respiratory distress (difficulty breathing, shortness of breath, wheezing, dyspnea)
- Open-mouth breathing
- Cough (dry, hacking)
- Pale mucous membranes (blue-ish gums)
- Exercise intolerance
- Lack of appetite
- Weight loss
Asthma is much less common in dogs than in cats; feline asthma is a well-documented disorder. The observable signs of asthma in dogs can range from mild to severe. Often, the exact asthmatic trigger is never identified. Some dogs become lethargic, stop eating and lose weight due to the discomfort caused by the condition. By the time this happens, the condition usually has progressed to chronic bronchitis, which is progressive and irreversible. In very severe cases, a dog may resort to open-mouth breathing and its gums and other mucus membranes may turn a purplish-blue from oxygen deprivation. When the consequences of allergic bronchitis become this severe, the dog needs immediate emergency veterinary care. Fortunately, allergic bronchitis in dogs is uncommon and normally can be effectively treated with medication. If your dog show signs of difficulty breathing accompanied by a dry, raspy cough, take him to your veterinarian as soon as possible.
Dogs At Increased Risk
Chronic allergic bronchitis, or asthma, is most common in older, small breed dogs of either gender, although large breed dogs should not be overlooked. Dogs exposed to particular environmental allergens are at an increased risk of developing this disorder; those allergens include cigarette or cigar smoke, wood burning stoves, fireplaces, carpet or floor cleaners and deodorizers and air fresheners.