The self-administration of inhaled beta agonist drugs during severe asthma

Interviews were conducted with 101 consecutive adult patients admitted to Wellington Hospital with a diagnosis of asthma to assess the extent to which beta agonist drugs are self-administered by asthmatic patients during severe asthma. The 99 patients prescribed an inhaled beta agonist were subdivided into two groups: group A comprising 79 patients prescribed a beta agonist for inhalation via an inhaler (metered dose aerosol or dry powder device) alone; group B comprising 20 patients prescribed beta agonist for inhalation via both an inhaler and nebuliser. In group A, the attacks of asthma lasted greater than 24 hours in 64/79 patients, and 22% of these patients reported taking more than 60 doses of their inhaler, and 52% more than 30 doses during the 24 hr period prior to admission. In group B, the attacks of asthma lasted greater than 24 h in 17/20 patients, and 35% of these patients self-administered their nebuliser more than six times, and 76% more than four times during the 24 h period prior to admission. In addition to their nebuliser use, these patients also took a median 23 doses of their inhaler during this 24 h period. This use of inhaled beta agonist contrasts with the recommended practice in both the USA and Europe, where most physicians recommend no more than 15 doses of a beta agonist as the maximal dose per day. We conclude that asthmatic patients in New Zealand self-administer high doses of inhaled beta 2 agonist drugs during severe exacerbations of asthma.