Abstract
Occupational asthma is the most common occupational respiratory disorder and accounts for 15% of cases of adult asthma. A recent systematic review of evidence and management has clarified patient care for General Practitioners (GPs) who are key professionals in early diagnosis. Exposure to respirable agents in the work environment by means of dust, water aerosol or gases, causes an allergic sensitisation process in the respiratory tract. Initial rhinitis and night cough may progress to patterns of work-related wheezing from two weeks to six months after starting employment. The absence of symptoms while on holiday or sick leave suggests the diagnosis. Serial peak flow recordings show characteristic patterns. Smoking and atopy have a variable influence on whether a worker will develop the disease with exposure. Early identification and removal from exposure is essential for the worker since it improves prognosis. Other workers will be at risk, and occupational hygienists are required to measure and improve the working environment by means of ventilation and extraction of toxic fumes. Workplaces with workers who are at risk of occupational asthma, such as paint sprayers, food processors, welders and animal handlers, require health surveillance programmes for new and existing employees, as well as reinforcement of the more important primary safety measures of environmental monitoring and respiratory protection. All clinicians responsible for asthma management need to be aware of the potential for occupational asthma in new cases of adult asthma or unexplained worsening of pre-existing asthma. Specialist help is required to confirm the diagnosis, which has substantial legal and economic implications for the worker and their employer.