ABC of Asthma: TREATMENT OF CHRONIC ASTHMABMJ 1995; 310 doi: https://doi.org/10.1136/bmj.310.6992.1459 (Published 03 June 1995) Cite this as: BMJ 1995;310:1459
- John Rees,
- John Price
The first line of treatment of mild intermittent asthma is one of the selective ß2-stimulants taken by inhalation. ß-stimulants are the most effective bronchodilator in asthma. They start to work quickly—salbutamol and terbutaline take effect within 15 minutes and last for four to six hours. If more than one daily dose is usually required then additional treatment must be considered. The dose response varies among patients as does the dose that will produce side effects, such as tremor. Patients should be taught to monitor their inhaler use and to understand that if they need it more or its effects lessen, these are danger signals. They indicate deterioration in asthmatic control and the need for further treatment.
Some patients worry that ß-stimulants may become slightly less effective with time, particularly if the dose is high. There is little evidence of appreciable tachyphylaxis for the airway effects in asthmatics. If it exists it is a minor effect that is quickly reversed either by stopping the treatment temporarily or by taking corticosteroids. Tremor, palpitations, and muscle cramps may occur but are rarely troublesome if the drug is inhaled and these adverse effects outside the lung often become less of a problem with continued treatment.
The regular use of ß-stimulants has in some studies been associated with increased bronchial reactivity, worsening asthma control, and accelerated decline of lung function. When the steps in the guidelines are followed, however, ß-stimulants are not used regularly unless needed for control of symptoms.
Long acting ß-stimulants
Long acting preparations of oral ß-agonists have been available for some years. They are effective in nocturnal asthma but are associated with more adverse effects than inhaled agents. The oral agent bambuterol, a prodrug of terbutaline, provides a …