Allergy, Asthma, Infant and Children | July 7, 2015 | Author: The Super Pharmacist
What is montelukast? A leukotriene is a molecule that is released by the body in response to allergens. When someone with seasonal allergies, hay fever, or asthma inhales an allergen (to which they are sensitive), the immune system responds by releasing a massive amount of leukotrienes. Leukotrienes then cause a number of physical responses. Leukotrienes makes smooth muscles in the lungs contract, increase the secretion of mucus in the airways, and stoke inflammation. As a result, the affected patients can have runny/stuffy nose, difficulty breathing, cough, and wheezing. Montelukast is a leukotriene inhibitor. In other words, the drug blocks these effects of leukotriene. The affected person still generates high levels of leukotrienes when they inhale an allergen, but montelukast essentially stands in the way of these leukotrienes and prevents them from affecting cells of the respiratory system.
Montelukast has been approved for use children for the treatment of allergic rhinitis, acute asthma, chronic asthma prevention, and exercised-induced bronchoconstriction (i.e. narrowing of the airways brought on by cardiovascular exercise). Montelukast is an oral medication available in chewable tablets and non-chewable tablets. These come in 4, 5, and 10 mg individual doses.
Administer dose at least 2 hours prior to exercise; additional doses should not be administered within 24 hours.
Special dosing guidelines cover the treatment of acute asthma exacerbation in young children. Acute asthma should not be treated with montelukast alone, but montelukast may be added to other asthma treatments, such as bronchodilators. Children ages 2 to 5 years may receive 4 mg/dose along with ongoing bronchodilator treatment.
Many parents have concerns about having their children take chronic doses of corticosteroids (i.e. “steroids”). This is because chronic corticosteroid use may cause several serious side effects, including growth suppression. It is important to note, however, that these reported serious side effects of chronic glucocorticoid use is far more common and more severe in those taking chronic oral or intravenous corticosteroids. Nevertheless, children who chronically use of inhaled corticosteroids may negatively affect bone formation and hormonal balance, sometimes seriously.
Montelukast and other leukotriene inhibitor drugs are not glucocorticoids. This makes leukotriene inhibitors an attractive choice for the treatment of children in whom chronic steroid use is undesirable. However, inhaled leukotriene inhibitors are less effective for the treatment of asthma than glucocorticoids in adults and children.
Few clinical studies have directly tested the efficacy and safety of montelukast or other leukotriene inhibitors in children under the age of two. Therefore, one must make an educated guess about the effects of montelukast in this age group.
In a group of 51 children between the ages of two and five years old with mild to moderate asthma exacerbation, montelukast plus a short-acting bronchodilator (salbutamol) significantly improved symptoms of the acute asthma attack compared to those receiving a bronchodilator alone. However, a certain portion of both montelukast (20.8%) and placebo (38.5%) groups required oral steroid treatment to help control symptoms. This suggests that montelukast is effective in reducing symptoms of an acute asthma attack, but more severe symptoms will require treatment with a steroid. Fewer children required corticosteroids if they were treated with montelukast (although this effect was not statistically significant in the paper).
In a randomised placebo-controlled trial with 689 children aged 2 to 5 years, 4 mg per day of montelukast for 12 weeks significantly reduced symptoms of asthma without adverse effects. Children had significantly less cough, less wheeze, less trouble breathing, and less limitation on activities when taking montelukast. The rate of adverse events was the same in both the montelukast and placebo groups.
At the very least, montelukast appears to be safe at doses of 4 mg per day in children as young as six months, since it is approved to treat allergic rhinitis at this dosage and age. Likewise, montelukast is considered safe in children 12 months old or older in the prevention of chronic asthma. This approval is based on results of placebo-controlled clinical studies. One study specifically assessed the safety of montelukast in 175 pediatric patients 6 to 23 months of age in a 6-week, double-blind, placebo-controlled clinical trial. Montelukast had possibly the same safety profile in this younger age group as it did in adults and children between the ages of 2 to 14. Certain adverse events occurred more often in the montelukast group than in the placebo group, namely:
Given what is currently known, or not known, about montelukast in very young patients less than 2 years, the drug should be used with caution. A physician should be consulted before starting montelukast therapy in any child, especially any child under the age of two. The drug has simply not been sufficiently tested in children under the age of six months, so it is unclear whether it is safe or effective in this age group. The drug is likely both safe and effective for the treatment of acute and chronic asthma in people six months old and older. Montelukast is demonstrated to be safer, but less effective than inhaled corticosteroids for treating asthma. Children with moderate or severe acute asthma attack likely will require at least short-term oral, intravenous, and/or inhaled corticosteroids despite their use of montelukast.
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