Prescription onlyLower-cost generic availableClass: Respiratory



Prescription onlyLower-cost generic availableClass: Respiratory
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Prevents breathing problems.

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Our bottom line

Singulair (Montelukast) has fewer side effects but doesn't work as well as steroid inhalers for asthma. It also helps with allergies.

Price and discounts
Best available price for 30 (10mg) tablets of montelukast


  • Prevents symptoms and improves lung function in children and adults with chronic asthma.
  • A single 10 mg dose improves exercise-induced asthma symptoms for up to 24 hours.
  • Fewer side effects compared to other asthma treatments.
  • Also relieves nasal allergy symptoms.
  • Effective pill alternative to corticosteroid inhalers.
People say this drug is:
557 reviews


  • You have to use Montelukast every day to control your symptoms.
  • Somewhat less effective than corticosteroid inhalers for asthma.
  • There's no generic available, so it can be expensive.
  • Can cause behavior changes, agitation, aggression, and difficulty sleeping for some people.
How it works

Singulair (Montelukast) is a leukotriene inhibitor. It lowers inflammation in your lungs and nasal passages to prevent asthma and relieve allergies.

What to expect when you take Singulair (montelukast) for Asthma

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Side effect rates for Singulair (montelukast)

3135 From clinical trials of Singulair / Asthma: Adults > 15 yrs (10 mg/day)
  • Headache
  • Flu
  • Pain, abdominal
  • Cough
  • Pain, dental
  • Gastroenteritis, infectious
  • Decreased liver function
  • Muscle weakness/fatiguea/fatigue
  • Fever
  • Indigestion

Risks and Warnings for Singulair (montelukast)

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    • Higher risk if:
    • Exercise-induced asthma
    • Other environmental triggers

    Singulair (Montelukast) is not used to treat sudden wheezing or asthma attack. You should have a fast-acting (rescue) inhaler with you all the time especially if you are prone to asthma during exercise. Talk to you doctor if your symptoms do not improve or seem to worsen while taking Singulair (Montelukast).

Common concerns from people taking Singulair (montelukast)

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  • Singulair (Montelukast) contains aspartame (phenylalanine). People who have phenylketonuria (PKU) can't break down the amino acid phenylalanine. It builds up and causes serious medical problems. If you have PKU, don't use this product.
Kidneys and liver
  • There are reports of liver injury in people taking Singulair (Montelukast) mostly in combination with other factors such as drugs, alcohol, and liver disease. If you have any of these risk factors, your doctor will need to check your liver function periodically.