Singulair (montelukast) is a prescription leukotriene receptor antagonist that prevents asthma symptoms and treats allergic rhinitis when taken daily. It is available as 10 mg tablets, 5 mg and 4 mg chewables, and oral granules (age approvals vary by formulation) . It does not act as a rescue inhaler. In 2020 the FDA added a Boxed Warning about rare but serious neuropsychiatric events and recommended limiting use for allergic rhinitis to patients who cannot be treated with other therapies. Common side effects include headache and abdominal pain; report any mood or behavior change to your clinician immediately.

What Singulair (montelukast) is

Singulair is the brand name for montelukast sodium, a leukotriene receptor antagonist (LTRA). It helps prevent asthma symptoms, exercise-induced bronchoconstriction, and treats allergic rhinitis (indoor and outdoor allergies) when prescribed by a clinician.

How it works and when it's used

Montelukast blocks leukotrienes - inflammatory chemicals the body makes after exposure to allergens - which reduces airway inflammation and constriction. Providers prescribe it as a daily preventive medicine, not as a rescue inhaler for acute asthma attacks.

Common formulations and age groups

Montelukast is available as 10 mg tablets for adults, 5 mg chewable tablets, 4 mg chewables, and oral granules. Specific age approvals differ by formulation; check your prescription label or ask your clinician for the correct product and dose for infants and children.

Dosage and timing

Most regimens are once daily. Many clinicians recommend taking montelukast in the evening for asthma control, though timing can be adjusted for convenience or symptom pattern. If you miss a dose, take it when you remember; do not double the next dose.

Important safety updates

In 2020 the U.S. Food and Drug Administration added a Boxed Warning to montelukast's label about rare but serious neuropsychiatric events. Reported problems include agitation, depression, sleep disturbances, hallucinations, and suicidal thoughts or behavior. Because of this risk, the FDA advises restricting use for seasonal or perennial allergic rhinitis to patients who cannot be adequately treated with other therapies. If you or a family member develops new or worsening mood or behavior changes, contact your clinician promptly.

Side effects and interactions

Common side effects reported include headache and abdominal pain. Less common but serious effects include mood and behavior changes (see above) and hypersensitivity reactions. Tell your clinician about all medicines and supplements you take; montelukast can be used with many other asthma controllers but should not replace fast-acting rescue inhalers during an attack.

When to call a clinician

Contact your clinician right away for severe side effects, new or worsening mental health symptoms, signs of an allergic reaction (hives, swelling, difficulty breathing), or suspected overdose. For an acute asthma attack, follow your emergency action plan and use your rescue inhaler; seek emergency care if symptoms do not improve.

Bottom line

Montelukast is an effective once-daily preventive medicine for some people with asthma and allergic rhinitis. Because of updated safety information about rare neuropsychiatric effects, discuss risks and alternatives with your clinician and monitor mood and behavior while taking it.
  1. Confirm current age-specific FDA approvals and recommended age ranges for each montelukast formulation (oral granules, 4 mg chewable, 5 mg chewable, 10 mg tablet).
  2. Verify the exact FDA language and recommendations regarding use of montelukast for allergic rhinitis and any post-2020 label updates.

FAQs about Singulair

Can montelukast be used during an acute asthma attack?
No. Montelukast is a preventive medication and does not replace short-acting rescue inhalers (e.g., albuterol) for acute bronchospasm. Use your emergency action plan and seek urgent care if needed.
What are the main safety concerns with montelukast?
The main safety concern added to the label is the risk of rare but serious neuropsychiatric events (agitation, depression, hallucinations, suicidal thoughts). Also report allergic reactions and other severe side effects to your clinician.
Is montelukast available over the counter?
No. Montelukast (Singulair) remains a prescription-only medicine in the United States.
How should I take missed doses?
If you miss a dose, take it when you remember. Do not take a double dose to make up for a missed one.
Should children take montelukast?
Montelukast is prescribed for children in specific formulations and doses. Age approvals vary by product; consult your pediatrician or pharmacist to confirm the correct formulation and dose.

News about Singulair

Are Singulair's Psychiatric Risks in Kids Overblown? - MedPage Today [Visit Site | Read More]

Asthma Drug Still Being Prescribed to Kids Despite Potential Mental Health Risks - Scientific American [Visit Site | Read More]

What to know about Singulair® and its effects on mental health - Nebraska Medicine [Visit Site | Read More]

New safety warnings for Singulair - Dispensing Doctors' Association [Visit Site | Read More]

No Risk of Neuropsychiatric AEs With Montelukast Over LABA Agents for Asthma, Allergic Rhinitis - HCPLive [Visit Site | Read More]

Warning over asthma drug after 500 neuropsychiatric reactions reported in young children - The Guardian [Visit Site | Read More]

Why a common asthma drug will now carry extra safety warnings about depression - The Conversation [Visit Site | Read More]

Urgent warning over common drug prescribed to Australians that could increase the risk of suicide - Daily Mail [Visit Site | Read More]