Increased levels of ozone, sulfur dioxide and nitrous dioxide can cause asthma exacerbations. It is important to recognize exposures in the workplace which may either cause or exacerbate a patient's asthma symptoms. Substances in the workplace which can cause asthma symptoms include animal products, wood dusts, plastic resin, biological enzymes, and metals. Patients often do not correlate their asthma symptoms with the workplace because symptoms often begin several hours after exposure. Workplace exposure should be considered in a patient whose asthma symptoms improve after several days away from work.
Appropriate treatment consists of removal of the offending agent.
Asthma symptoms may persist in some patients even after they are no longer exposed. All warm blooded animals can produce urine, feces, dander and saliva that can cause allergic reaction. If a patient appears to have a sensitivity to animal allergens then the most appropriate measure is removal of the animal. If this is not possible then the animal should be kept out of the patient's room, the patient's bedroom door should be kept closed when possible and the pet should be kept away from any upholstered furniture. They occur in mattresses, pillows, carpets, upholstery, bed covers and toys.