How to Take Singulair: Side Effects, Dosage
How to take Singulair: dosage guidelines, common side effects, and important warnings including the FDA black box warning for neuropsychiatric events.
Not medical advice. Speak with a healthcare professional before using any medication.
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Updated Feb, 15
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Information sourced from FDA-approved prescribing information and peer-reviewed medical references.
How to Take Singulair
How to Take Singulair
Per FDA-approved prescribing information, Singulair (montelukast) is taken once daily in the evening and may be taken with or without food. Use the form and dose that corresponds to the patient's age:
- Adults and teens 15 years and older: 10 mg tablet, swallowed whole, once each evening.
- Children 6–14 years: 5 mg chewable tablet, chewed fully, once each evening.
- Children 2–5 years: 4 mg chewable tablet, chewed fully, once each evening.
- Children 12–23 months: 4 mg oral granules once each evening.
Using oral granules:
- May be given directly into the child's mouth or mixed with a small amount of soft food such as applesauce, mashed carrots, or ice cream.
- Use the mixture immediately; do not store it.
- Do not mix granules with liquids; liquids may be given after the dose.
General guidance:
- Taking it at the same time each night supports consistent dosing.
- If a dose is missed, take it when remembered unless it is close to the next evening dose — in that case, skip the missed dose.
- Per prescribing information, continue daily use even when symptoms are absent unless instructed otherwise by your clinician.
Warnings Before Taking Singulair
- Black Box Warning — Neuropsychiatric Events: Per FDA-approved prescribing information, montelukast (a leukotriene modifier) carries a black box warning for serious neuropsychiatric events including suicidal thoughts, agitation, depression, and hallucinations. Discuss personal or family history of mental health conditions with your prescriber before starting.
- Per FDA-approved prescribing information: Inform your prescriber of any history of mood changes, depression, or anxiety prior to use.
- Per FDA-approved prescribing information: Disclose any liver disease or prior abnormal liver test results to your clinician.
- Per FDA-approved prescribing information: Provide a complete medication list, including all OTC drugs and supplements, especially those used for allergies or asthma.
- Per FDA-approved prescribing information: Inform your clinician if you are pregnant or breastfeeding before use.
- Per FDA-approved prescribing information: Do not use if you have had a prior allergic reaction to montelukast.
Singulair Side Effects
Common
Mild
Headache
Neuropsychiatric Events (Black Box Warning): Per FDA-approved prescribing information, montelukast carries a black box warning for serious neuropsychiatric events including suicidal thoughts, agitation, depression, and hallucinations. Contact your prescriber immediately if you or the patient experience any mood or behavioral changes.
Per FDA-approved prescribing information, headache is a reported adverse reaction with montelukast. It is generally described as mild to moderate and may occur during initial use.
Normally lasts for:
2–6 hours
Common
Mild
Stomach Pain
Per FDA-approved prescribing information, abdominal pain is a reported adverse reaction with montelukast. Taking the dose with a small amount of food may help reduce stomach discomfort.
Normally lasts for:
1–4 hours
Common
Mild
Fatigue
Per FDA-approved prescribing information, fatigue is a reported adverse reaction with montelukast. This effect is generally described as mild.
Normally lasts for:
2–8 hours
Common
Mild
Upper Respiratory Infection
Per FDA-approved prescribing information, upper respiratory infection symptoms — including congestion and sore throat — are among the reported adverse reactions associated with montelukast use.
Normally lasts for:
24–48 hours
Uncommon
Mild
Diarrhea
Per FDA-approved prescribing information, diarrhea is a reported adverse reaction with montelukast.
Normally lasts for:
4–12 hours
Rare
Serious
Mood Changes
Per FDA-approved prescribing information, mood and behavior changes — including irritability and restlessness — are reported adverse reactions with montelukast. This is related to the black box warning for neuropsychiatric events. Notify your prescriber promptly if any mood or behavioral changes occur.
Normally lasts for:
Several hours to 1 day
Contact Us for a Personalized Care Plan
Have questions about compounding? Contact Voshell's Pharmacy — we prepare patient-specific medications pursuant to valid prescriptions from your licensed prescriber.
What If You Forgot to Take Singulair
What If You Forgot to Take Singulair?
Per FDA-approved prescribing information, if a dose is missed, take it as soon as remembered. If it is close to the next scheduled evening dose, skip the missed dose and resume the regular schedule.
- Do not double up to make up for a missed dose.
- If doses are frequently missed, a consistent nightly reminder may help maintain adherence.
What If You Took Too Much Singulair
What If You Took Too Much Singulair (By Accident)?
Contact Poison Control immediately at 1-800-222-1222 (U.S.) if you suspect an overdose, even if no symptoms are present. Emergency services (911) should be contacted if the person is unresponsive or severely symptomatic.
- Per available data: Clinical experience with montelukast overdose is limited; specific toxic symptoms are not well characterized in published literature. Poison Control can provide guidance based on the amount ingested and individual circumstances.
- Do not take additional doses until evaluated by a medical professional.
- Bring the medication bottle or know the exact dose taken when contacting Poison Control or seeking care.
How Much Does Singulair Cost
How Much Does Singulair Cost With Insurance?
With insurance coverage, montelukast (the generic form of Singulair) is commonly placed on a lower formulary tier. Actual costs depend on your specific insurance plan, formulary tier, deductible status, and preferred pharmacy network. Contact your insurance plan or pharmacy directly for your actual out-of-pocket cost. FSA/HSA funds may be applicable for covered medications.
Pricing information is subject to change. This is not a guarantee of coverage or cost.
How Much Does Singulair Cost without Insurance
Cost of Singulair Without Insurance
Without insurance, the cost of montelukast (generic) and brand-name Singulair varies by pharmacy, dosage strength, and quantity. Prices differ between retail pharmacies, discount programs, and online pharmacy services. Contact your local pharmacy or a pharmacy discount program directly for current pricing. FSA/HSA funds may be used for eligible prescription medications.
Pricing information is subject to change and may vary significantly by location and pharmacy.
