montelukast, Singulair (cont.)

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PRESCRIBED FOR: Montelukast is used for the treatment of asthma, seasonal allergic rhinitis, and prevention of exercise induced bronchospasm (narrowing of airways). Montelukast begins working after 3 to 14 days of therapy; It should not be used for the treatment of an acute asthmatic attack.

DOSING: The recommended dose of montelukast in adults is 10 mg daily for treating asthma and allergic rhinitis and 10 mg two hours before exercising for prevention of exercise induced bronchospasm. Montelukast should be taken in the evening with or without food when used for asthma or allergic rhinitis. The 4 and 5 mg tablets are used in children.

DRUG INTERACTIONS: Phenobarbital, rifampin, and carbamazepine (Tegretol, Tegretol XR, Equertro, Carbatrol) may decrease blood concentrations of montelukast. This may reduce the effect of montelukast.

PREGNANCY: Montelukast crosses the placenta into the fetus following oral administration to animals, but there have been no adequate studies in pregnant women to determine the effects on the fetus. Physicians may prescribe zafirlukast during pregnancy if it is felt that its benefits outweigh the potential but unknown risks to the fetus.

NURSING MOTHERS: Studies in animals have shown that montelukast is excreted in milk; however, it is not known if montelukast is secreted into breast milk in humans.

SIDE EFFECTS: The most common side effects with montelukast are headache, dizziness, abdominal pain, sore throat, and rhinitis (inflammation of the inner lining of the nose). Wheezing, cough, rash, restlessness, tremor, and nausea may also occur. Elevated liver enzymes, suicidal behavior, fluid retention, depression, and hallucinations have also been reported.

Reference: FDA Prescribing Information


Last Editorial Review: 3/19/2012



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