Israel Medical Association Journal

Background: Based on the outcome of several randomized controlled trials, the orally active leukotriene receptor antagonist montelukast (Singulair®, Merck) has been licensed for treatment of asthma. The drug is favored for treating childhood asthma, where a therapeutic challenge has arisen due to poor compliance with inhalation therapy.

Objectives: To assess the efficiency of and satisfaction with Singulair® in asthmatic children under real-life conditions.

Methods: Montelukast was prescribed for 6 weeks to a cohort of 506 children aged 2 to 18 years with mild to moderate persistent asthma, who were enrolled by 200 primary care pediatricians countrywide. Four clinical correlates of childhood asthma – wheeze, cough, difficulty in breathing, night awakening – were evaluated from patients' diary cards.

Results: Due to under-treatment by their physicians, almost 60% of the children were not receiving controller therapy at baseline. By the end of the study, which consisted of montelukast treatment, a significant improvement over baseline was noted in asthma symptoms and severity, as well as in treatment compliance. The participating pediatricians and parents were highly satisfied with the treatment.

Conclusions: The results of this extensive study show that the use of montelukast as monotherapy in children presenting with persistent asthma resulted in a highly satisfactory outcome for themselves, their parents and their physicians.
 

Background: The anti-inflammatory effect of montelukast, a leukotriene receptor antagonist, in patients with bronchial asthma is not entirely clear. Basophils can release a variety of mediators, including histamine and leukotriens, which most likely play an active part in the late allergic response.

Objectives: To study the effect of montelukast (10 mg/day) on histamine and cysteinyl leukotriene release from basophils taken from 12 mild atopic asthmatic patients who were given the drug for 4 weeks.

Methods: Basophils were withdrawn at baseline, and after 48 hours, 1 week, and 4 weeks of therapy. Histamine was measured by a radioenzymatic method and leukotrienes by immunologic assay. Histamine and cysLT release was measured spontaneously and following stimulation with interleukin-3 and anti-immunoglobulin E. Spirometry and symptom score were measured before and during treatment.

Results: During the treatment with montelukast there were no significant changes in spontaneous, IL-3 and anti-IgE‑induced histamine release. cysLT release decreased significantly only after 4 weeks of treatment (from 2899 ± 550 pg/ml at baseline to 2225 ± 430 pg/ml at 4 weeks, P = 0.02).

Conclusions: Montelukast does not seem to affect the release of histamine from basophils but mildly inhibits the cysLT release seen after 4 weeks of treatment.

Background: Leukotriene antagonist therapy in asthmatic patients alleviates symptoms and improves exercise tolerance, however the effect of these drugs on bronchial provocation tests and exhaled nitric oxide levels are less clearly established.

Objective: To determine the effect of montelukast treatment on airway hyperresponsiveness to exercise, methacholine and adenosine-5’-monophosphate and on exhaled nitric oxide levels in steroid-naive asthmatics.

Methods: Following a 2 week run-in period, 20 mild to moderate asthmatics were enrolled in an open label 6 week trial of oral montelukast-sodium therapy. Bronchial hyperreactivity (exercise, methacholine and adenosine-5’-monophosphate challenges) and exhaled nitric oxide levels were measured before and after the 6 week period.

Results: Montelukast treatment resulted in a significant improvement in exercise tolerance: median DFEV₁ 20.0% (range 0–50) prior to treatment vs. 15.0% (range 0–50) post-treatment (P = 0.029). A significant difference was also observed for exhaled NO[1] following therapy: median NO 16.0 ppb (range 7–41) vs. 13.0 (range 4.8–26) (P = 0.016). No change was seen in baseline lung function tests (FEV₁, MEF₅₀) or in the bronchial responsiveness (PC₂₀) for methacholine and adenosine-5’-monophosphate.

Conclusions: This study demonstrates that the leukotriene antagonist, montelukast-sodium, reduces bronchial hyperreactivity in response to exercise and reduces exhaled nitric oxide levels but has little effect on bronchial responsiveness to methacholine and adenosine challenges.