Identify the usage of montelukast (Singulair) and how it is normally administered.

Montelukast, commonly known by its brand name Singulair, is classified as a leukotriene receptor antagonist. This medication is primarily used in the management of asthma and to relieve symptoms associated with seasonal allergies. By blocking leukotrienes, which are substances in the body that can trigger asthma and allergic responses, montelukast helps reduce inflammation in the airways, making it easier for patients to breathe.

Most typically, montelukast is administered once a day in the evening. This timing is particularly beneficial for asthma management, as it aligns with times when asthma symptoms might worsen, such as during the night or early morning. The once-daily dosage is convenient and helps maintain consistent therapeutic levels in the bloodstream to provide effective control over symptoms.

In the context of the other choices, montelukast is not indicated for hypertension, it is not an antibiotic, nor a phenothiazine used for anxiety. These distinctions underscore the unique role montelukast plays in respiratory health and emphasize the importance of its correct usage and administration schedule for optimal patient outcomes.