Can Fam Physician. 2000 Jan;46:86-99.
Montelukast (Singulair), an antiasthma drug belonging to the leukotriene antagonist family, has two indications: as adjunctive treatment for mild-to-moderate chronic asthma when regular inhaled steroid therapy and short-acting inhaled beta2 stimulants "on demand" are inadequate; and in prevention of effort-induced asthma. The clinical file on montelukast contains no methodologically acceptable comparisons with reference treatments. Several placebo-controlled trials have shown the efficacy of montelukast, with improvement in clinical scores and respiratory function tests in those with chronic asthma and prevention of effort-induced asthma. For chronic asthma, montelukast has not been compared with oral or inhaled long-acting beta2 stimulants or with sustained-release theophylline in patients inadequately controlled by steroid therapy. For effort-induced asthma, only two trials have compared montelukast with salmeterol. On the basis of preliminary results, the authors of both studies concluded that montelukast was superior. Clinical trials showed no clear difference in the frequency of side effects in patients taking montelukast and patients taking placebo. Montelukast, however, might be associated with Churg-Strauss syndrome in rare cases. Montelukast is expensive.