Montelukast Dosage: What You Need to Know About Taking It Safely

When you're prescribed montelukast, a leukotriene receptor antagonist used to control asthma and allergic rhinitis. Also known as Singulair, it works by blocking substances in your body that cause airway swelling and tightening. Getting the montelukast dosage right matters—not just for symptom control, but to avoid side effects like mood changes, headaches, or stomach issues that some people report.

For adults and teens 15 and older, the standard dose is one 10 mg tablet taken once daily, usually in the evening. That timing helps block nighttime asthma symptoms and allergic reactions that often flare up while you sleep. For kids, it’s different: children 6 to 14 years old take a 5 mg chewable tablet, while those 2 to 5 years old get a 4 mg chewable or oral granule packet. Babies as young as 12 months can use the granules mixed with food like applesauce or baby formula—no water needed. If you’re using montelukast for allergies alone, not asthma, your doctor might still recommend taking it at night, since allergens like pollen or dust build up during the day and affect you overnight.

Don’t double up if you miss a dose. Just skip it and go back to your regular schedule. Never use montelukast as a rescue inhaler during an asthma attack—it won’t work fast enough. Always keep your quick-relief inhaler handy. People with liver problems might need a lower dose, and if you’re on other meds like phenobarbital or rifampin, they can make montelukast less effective. That’s why your doctor checks your full list of medications before starting you on it.

Some users report trouble sleeping, irritability, or even depression while taking montelukast. The FDA has warned about these neuropsychiatric effects, so if you or your child start acting unusually—having nightmares, feeling anxious, or showing signs of aggression—call your doctor right away. It’s rare, but it happens. And if you’re using montelukast for exercise-induced asthma, take it at least 2 hours before working out. Don’t take it right before or after, because timing affects how well it works.

Montelukast isn’t a cure, but it’s a steady, daily shield. It doesn’t replace steroids or inhalers, but it helps reduce how often you need them. You’ll often see it paired with inhaled corticosteroids in treatment plans for moderate to severe asthma. And because it’s taken orally, it’s easier for kids or people who struggle with inhalers. If you’ve tried antihistamines for allergies and still feel congested or wheezy, montelukast might be the next step your doctor suggests.

What you’ll find below are real, practical comparisons and guides from patients and doctors who’ve lived with asthma, allergies, and the daily choices around meds like montelukast. You’ll see how it stacks up against other treatments, what side effects people actually experience, how dosage changes for kids, and what to do if it doesn’t seem to be working. No fluff. Just what you need to take control—safely and smartly.