Just as it occurs in humans, asthma can also occur in dogs. In cases of dog asthma, the cause of an asthmatic condition is relatively the same as it is in human asthma cases. Asthma is classified as a symptom of a severe allergic reaction, which probably has one or several triggers that may induce an asthma attack. While the specific cause of each dog's allergic reaction may differ, asthmatic symptoms remain relatively similar (coughing, wheezing, lethargy, etc).
An asthma attack is usually induced by any number of airborne irritants. When a dog inhales one of these irritants, the lung passages (which may already be sensitive, inflamed or swollen) experience an automatic muscle constriction. This results in narrow air passages, and inhibits regular breathing.
This constriction of the muscles around air passages is called "bronchoconstriction". In addition to this, the air passages may begin to produce excess mucus to combat the inhaled irritant, further inhibiting breathing.
Some of the most common airborne irritants that may induce an asthma attack in dogs include:
Just as many humans may have adverse respiratory affects from exposure to cigarette smoke, this may also cause asthma in dogs. If you believe that cigarette smoke may be the cause of your dog's asthma, try to limit any smoking to the outdoors, or quit smoking altogether. If you have guests or house-mates who smoke, try to encourage them to smoke when your dog is not in the area.
This is a very common airborne irritant that causes respiratory distress for humans, and may also induce asthma in dogs. If you believe pollen to be the cause of your dog's asthma, try investing in a high-quality air filter for your home.
Household dust is sometimes the by-product of dust mites, and may induce asthma in dogs. As with pollen, this can be prevented (to an extent) with a high-quality air filter.
In some cases, the cause of your dog's asthmatic condition may be the result of a household spray, treatment or product that you use. Some household cleaners, especially those with a spray function, may leave airborne particles that might cause an allergic reaction in your dog. If you are unable to identify the specific irritant that causes asthma attacks in your dog, try switching household cleaning products.