- Asthma affects about 300 million individuals worldwide. Although most patients have mild disease, the majority of them do not have good control and are at risk of exacerbations. Poor compliance with regular maintenance treatment is a considerable problem and is believed to be the main reason for poor control in asthma. In patients with moderate to severe asthma, maintenance and as-needed treatment with one inhaler containing an inhaled corticosteroid (ICS) and the long-acting inhaled β2-agonist formoterol has been proved effective in reducing the risk of severe exacerbations. Recently, the results of 2 large double-blind randomized trials assessing the use of as-needed budesonide/formoterol in patients with mild asthma, who had indications for a regular controller treatment, were published. In comparison with as-needed terbutaline treatment, as-needed budesonide/formoterol treatment improved symptom control and reduced the risk of exacerbations. In comparison with regular ICS treatment, exacerbation rates were similar, but regular treatment schedule was associated with better asthma control (despite a higher cumulative ICS dose). The results of these trials have shown that as-needed budesonide/formoterol therapy has acceptable efficacy in mild asthma and may be viewed as a therapeutic option for these patients. As-needed treatment may be preferred by patients who fear the side effects of ICS treatment or by those who experience difficulty in following a fixed-dose regimen. Patients with mild asthma wishing to achieve optimal asthma control may prefer regular maintenance treatment with an ICS.