As Mary @Hankmacaw pointed out, oxygen therapy is one of the best treatments for this condition.
Below, I've taken an insert from one my wife's vet manuals. It's interesting read.
A respiratory condition similar to chronic obstructive pulmonary disease (COPD) affecting macaws and some other spieces (but primarily Blue and Gold macaws) has been recognized for several decades. These birds often have a history of being housed in poorly ventilated environments with birds that produce large amounts of powderdown (such as cockatoos and African Grey parrots). This does not mean that all macaws must be kept in separate areas from cockatoos or African Greys, but good air circulation and environmental hygiene is needed.
Birds that develop this hypersensitivity may also have secondary bacterial or fungal infections. Your veterinarian may need to do several procedures to determine whether your macaw’s respiratory condition is due to this hypersensitivity or to other causes. A blood cell count and x-rays are often performed. A tracheal wash may be necessary to determine if a combination of these diseases is present, and to select the appropriate treatment. A lung biopsy is the only way to confirm the diagnosis.
Initially,
the best treatment for a bird that is in respiratory distress from this condition is oxygen. Your veterinarian may also consider the use of glucocorticoids or other anti-inflammatory drugs. Longterm management requires optimal air quality and ventilation. A good air filter (such as a HEPA filter) located near the cage is invaluable. Repeat crises may occur and necessitate rehospitalization and treatment, but a change of environment and increased ventilation will reduce the likelihood of severe relapse.
Some permanent lung damage is usually present, and exercise intolerance often persists due to interstitial fibrosis (scarring) of the lungs. Affected birds may a shorter lifespan.
Polycythemia, an increase in the percentage of red blood cells, is a very common finding on the blood work and may be the best method to screen for this disease before it becomes a noticeable problem.
