Several types of industrious and environmental hazardous substances in a hospital setting might trigger or exacerbate the development of asthma. The respiratory therapists are at high risk of developing work-related asthma, including occupational asthma and work-exacerbated asthma. Nevertheless, only few epidemic studies and health surveillance have found that respiratory therapists have more excessive risk at asthma or breathing problems than other health care workers. Asthma among respiratory therapists may be associated with medical instrument cleaning, use of powered latex gloves, bacterial-based environment and second-hand aerosol administration. However, these higher possibilities currently do not have a solid explanation and hard evidence to prove. Further studies in this field may provide new insights into the pathophysiology of work-related asthma among respiratory care practitioners, and provide optimal management of these patients.