Singulair 4mg Oral Granules
WARNING: For all uses of this drug:Severe mental health problems have happened with this drug or after it has been stopped. These problems include depression or suicidal thoughts or actions. These problems can happen in people with and without a history of mental or mood problems. Watch people who take this drug closely. Call the doctor right away if any changes in mood or behavior that are new or worse occur. This includes signs like depression; thoughts or actions of suicide; not able to focus; bad or strange dreams; anxiety; hallucinations (seeing or hearing things that are not there); memory problems; sleep walking; stuttering; shakiness; trouble sleeping; trouble controlling body movements; or feeling agitated, confused, irritable, or restless. Talk with the doctor to be sure that the benefits of this drug are more than the risks.For allergic reasons:This drug must only be used when other drugs cannot be used or have not worked. If you have questions, talk with the doctor. @ COMMON USES: It is used to prevent breathing problems that happen with exercise.It is used to treat or prevent asthma.It is used to ease allergy signs.It may be given to you for other reasons. Talk with the doctor.For breathing problems:Do not use this drug to treat intense flare-ups of shortness of breath. Use a rescue inhaler. If you have questions, talk with the doctor.
Drug Class
Antiasthmatic, Antiallergic
Pharmacologic Class
Leukotriene Receptor Antagonist (LTRA)
Pregnancy Category
Category B
FDA Approved
Feb 1998
DEA Schedule
Not Controlled
Overview
What is this medicine?
Montelukast is a medicine that helps prevent asthma attacks and control symptoms of allergies like sneezing and runny nose. It works by blocking natural substances in your body called leukotrienes, which can cause inflammation and narrowing of the airways. This medicine is not for sudden asthma attacks.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your medication and follow the instructions closely. You can take this medication with or without food.
Preparing Your Dose
The granules can be placed directly in your mouth or mixed with a small amount of cold or room temperature applesauce, baby formula, breast milk, mashed carrots, rice, or ice cream. However, do not mix the granules with any other liquids. Only open the packet when you are ready to take your dose, and take it within 15 minutes of opening. Do not store the opened packet for future use.
Continuing Your Treatment
Continue taking your medication as directed, even when you are not experiencing symptoms. If you are taking this medication to prevent breathing problems that occur with exercise, take it at least 2 hours before exercising. If you are taking this medication for asthma, take it in the evening.
Storing Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Do not store it in a bathroom. Keep the medication in its original container.
Missing a Dose
If you miss a dose, skip it and return to your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed dose.
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your medication and follow the instructions closely. You can take this medication with or without food.
Preparing Your Dose
The granules can be placed directly in your mouth or mixed with a small amount of cold or room temperature applesauce, baby formula, breast milk, mashed carrots, rice, or ice cream. However, do not mix the granules with any other liquids. Only open the packet when you are ready to take your dose, and take it within 15 minutes of opening. Do not store the opened packet for future use.
Continuing Your Treatment
Continue taking your medication as directed, even when you are not experiencing symptoms. If you are taking this medication to prevent breathing problems that occur with exercise, take it at least 2 hours before exercising. If you are taking this medication for asthma, take it in the evening.
Storing Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Do not store it in a bathroom. Keep the medication in its original container.
Missing a Dose
If you miss a dose, skip it and return to your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed dose.
Lifestyle & Tips
- Take this medicine once daily in the evening, even if your child feels well.
- Do not use this medicine for sudden asthma attacks; use a fast-acting inhaler (rescue inhaler) as prescribed.
- Administer granules directly into the mouth, or mix with a spoonful of soft food (e.g., applesauce, carrots, rice, or ice cream), or in breast milk or infant formula. Do not mix in other liquids. Administer within 15 minutes of opening the packet.
- Do not store mixed granules for later use.
- Continue to use other asthma medications as prescribed by your doctor.
- Be aware of and report any changes in mood or behavior, such as agitation, aggression, depression, or thoughts of self-harm, to your doctor immediately.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Not typically used for adults; adult dose is 10mg tablet once daily in the evening.
Pediatric Dosing
Neonatal:
Not established
Infant:
For asthma and/or allergic rhinitis: 4 mg oral granules once daily in the evening for infants 6 to 23 months of age.
Child:
For asthma and/or allergic rhinitis: 4 mg oral granules once daily in the evening for children 2 to 5 years of age. (Note: 5mg chewable tablet for 6-14 years).
Adolescent:
Not typically used for adolescents; adolescent dose is 5mg chewable tablet or 10mg tablet once daily in the evening.
Dose Adjustments
Renal Impairment:
Mild:
No adjustment needed.
Moderate:
No adjustment needed.
Severe:
No adjustment needed.
Dialysis:
No adjustment needed; montelukast is highly protein bound and not removed by dialysis.
Hepatic Impairment:
Mild:
No adjustment needed.
Moderate:
No adjustment needed.
Severe:
Not studied; use with caution.
Pharmacology
Mechanism of Action
Montelukast is a selective and orally active leukotriene receptor antagonist that specifically inhibits the cysteinyl leukotriene CysLT1 receptor. Cysteinyl leukotrienes (LTC4, LTD4, LTEE4) are potent inflammatory eicosanoids released from various cells, including mast cells and eosinophils. These leukotrienes bind to CysLT1 receptors found in the human airway and on other pro-inflammatory cells, causing bronchoconstriction, mucus secretion, vascular permeability, and eosinophil recruitment. Montelukast antagonizes the effects of these leukotrienes, thereby improving asthma control and allergic rhinitis symptoms.
Pharmacokinetics
Absorption:
Bioavailability:
Not available (oral granules)
Tmax:
2-4 hours (for 4mg granules in children 2-5 years)
FoodEffect:
Food does not significantly affect the bioavailability of montelukast oral granules. Can be administered directly into the mouth, or mixed with a spoonful of soft food (e.g., applesauce, carrots, rice, or ice cream), or in breast milk or infant formula. Do not mix in other liquids. Administer within 15 minutes of opening the packet.
Distribution:
Vd:
8-11 liters
ProteinBinding:
>99%
CnssPenetration:
Limited
Elimination:
HalfLife:
2.7-5.5 hours
Clearance:
Not available
ExcretionRoute:
Primarily biliary (feces)
Unchanged:
<0.2% in urine
Pharmacodynamics
OnsetOfAction:
Within 1 day (for clinical effect in asthma)
PeakEffect:
Not precisely defined for clinical effect, but peak plasma concentrations reached in 2-4 hours.
DurationOfAction:
Approximately 24 hours (allowing once-daily dosing)
Confidence:
Medium
Safety & Warnings
BLACK BOX WARNING
Serious neuropsychiatric events have been reported with the use of montelukast. These include agitation, aggression, depression, sleep disturbances, and suicidal thoughts and behavior. Patients and caregivers should be advised to be alert for these changes and to seek medical advice if they occur.
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of a severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis), such as:
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Red or irritated eyes
+ Sores in the mouth, throat, nose, or eyes
New or worsening trouble breathing
Fever
Flu-like symptoms
Sinus pain
Abnormal burning, numbness, or tingling sensations
Ear pain
Other Possible Side Effects
Like all medications, this drug can cause side effects. However, many people experience no side effects or only mild ones. If you encounter any of the following side effects or any other symptoms that concern you or do not go away, contact your doctor:
Headache
Stomach pain or diarrhea
Signs of a common cold
Cough
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of a severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis), such as:
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Red or irritated eyes
+ Sores in the mouth, throat, nose, or eyes
New or worsening trouble breathing
Fever
Flu-like symptoms
Sinus pain
Abnormal burning, numbness, or tingling sensations
Ear pain
Other Possible Side Effects
Like all medications, this drug can cause side effects. However, many people experience no side effects or only mild ones. If you encounter any of the following side effects or any other symptoms that concern you or do not go away, contact your doctor:
Headache
Stomach pain or diarrhea
Signs of a common cold
Cough
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Worsening asthma symptoms
- New or worsening neuropsychiatric symptoms (e.g., agitation, aggression, anxiety, depression, disorientation, abnormal dreams, hallucinations, insomnia, irritability, memory impairment, obsessive-compulsive symptoms, restlessness, somnambulism, suicidal ideation and behavior, tremor, tic)
- Rash
- Swelling of the face, lips, tongue, and/or throat (signs of allergic reaction)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. This information will help your doctor and pharmacist assess potential interactions between this medication and other substances you are taking.
* Any existing health problems, as this medication may interact with certain conditions.
To ensure your safety, it is crucial to verify that it is safe to take this medication with all your current medications and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. This information will help your doctor and pharmacist assess potential interactions between this medication and other substances you are taking.
* Any existing health problems, as this medication may interact with certain conditions.
To ensure your safety, it is crucial to verify that it is safe to take this medication with all your current medications and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
Precautions & Cautions
Important Information About Your Medication
It is crucial that you inform all of your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
If you are pregnant, planning to become pregnant, or are breastfeeding, you must discuss the potential benefits and risks of this medication with your doctor, as they relate to both you and your baby.
Special Considerations for Breathing Problems
If you experience worsening breathing problems, or if your rescue inhaler becomes less effective or needs to be used more frequently, contact your doctor immediately.
If you are taking this medication for asthma or allergies, do not take an additional dose to prevent exercise-induced breathing problems.
If you have asthma and notice that aspirin exacerbates your condition, it is recommended that you avoid taking aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, while using this medication.
Transitioning from Steroid Medication
If you are switching to this medication from a steroid, do not abruptly stop taking the steroid. Instead, consult with your doctor, as the steroid dosage may need to be gradually reduced to minimize potential side effects.
It is crucial that you inform all of your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
If you are pregnant, planning to become pregnant, or are breastfeeding, you must discuss the potential benefits and risks of this medication with your doctor, as they relate to both you and your baby.
Special Considerations for Breathing Problems
If you experience worsening breathing problems, or if your rescue inhaler becomes less effective or needs to be used more frequently, contact your doctor immediately.
If you are taking this medication for asthma or allergies, do not take an additional dose to prevent exercise-induced breathing problems.
If you have asthma and notice that aspirin exacerbates your condition, it is recommended that you avoid taking aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, while using this medication.
Transitioning from Steroid Medication
If you are switching to this medication from a steroid, do not abruptly stop taking the steroid. Instead, consult with your doctor, as the steroid dosage may need to be gradually reduced to minimize potential side effects.
Overdose Information
Overdose Symptoms:
- Abdominal pain
- Somnolence (drowsiness)
- Thirst
- Headache
- Vomiting
- Psychomotor hyperactivity
What to Do:
Seek immediate medical attention or call a poison control center (1-800-222-1222). Treatment is supportive.
Drug Interactions
Moderate Interactions
- Phenobarbital (may decrease montelukast plasma concentrations)
- Rifampin (may decrease montelukast plasma concentrations)
Monitoring
Baseline Monitoring
Baseline asthma/allergic rhinitis symptoms
Rationale: To establish a starting point for assessing treatment efficacy.
Timing: Prior to initiation of therapy.
Routine Monitoring
Asthma symptom control (e.g., frequency of wheezing, shortness of breath, nocturnal awakenings)
Frequency: Regularly, at follow-up visits (e.g., every 1-3 months initially, then every 3-12 months)
Target: Improved symptom control, reduced need for rescue medication.
Action Threshold: Persistent or worsening symptoms may indicate need for dose adjustment or alternative therapy.
Allergic rhinitis symptom control (e.g., sneezing, rhinorrhea, nasal congestion)
Frequency: Regularly, at follow-up visits.
Target: Improved symptom control.
Action Threshold: Persistent or worsening symptoms.
Neuropsychiatric symptoms (e.g., agitation, aggression, depression, sleep disturbances, suicidal thoughts/behavior)
Frequency: Ongoing, at every visit and through patient/caregiver reporting.
Target: Absence of new or worsening neuropsychiatric symptoms.
Action Threshold: Any new or worsening neuropsychiatric symptoms warrant immediate evaluation and consideration of discontinuation.
Symptom Monitoring
- Worsening asthma symptoms
- New or worsening neuropsychiatric symptoms (e.g., agitation, aggression, anxiety, depression, disorientation, abnormal dreams, hallucinations, insomnia, irritability, memory impairment, obsessive-compulsive symptoms, restlessness, somnambulism, suicidal ideation and behavior, tremor, tic)
- Signs of Churg-Strauss syndrome (e.g., eosinophilia, vasculitic rash, worsening pulmonary symptoms, cardiac complications, and/or neuropathy)
Special Patient Groups
Pregnancy
Montelukast is Pregnancy Category B. Studies in animals have not shown harm to the fetus, but there are no adequate and well-controlled studies in pregnant women. Use during pregnancy only if clearly needed and the potential benefit outweighs the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
No increased risk of major birth defects observed in human studies.
Second Trimester:
No specific risks identified.
Third Trimester:
No specific risks identified.
Lactation
Montelukast is excreted in human milk. Caution should be exercised when montelukast is administered to a nursing woman. The decision to discontinue nursing or to discontinue the drug should be made taking into account the importance of the drug to the mother.
Infant Risk:
L3 (Moderate risk). Monitor breastfed infant for potential adverse effects (e.g., diarrhea, rash, irritability).
Pediatric Use
Montelukast 4mg oral granules are specifically approved for infants 6 to 23 months of age and children 2 to 5 years of age for asthma and/or allergic rhinitis. Safety and efficacy in infants younger than 6 months have not been established. Neuropsychiatric events have been reported in pediatric patients.
Geriatric Use
Clinical studies of montelukast did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. No overall differences in safety or effectiveness were observed between elderly and younger subjects. No dosage adjustment is necessary based on age.
Clinical Information
Clinical Pearls
- Montelukast is a prophylactic and chronic treatment for asthma and allergic rhinitis; it is NOT for acute asthma attacks.
- Administer the oral granules directly into the mouth or mixed with a spoonful of soft food (e.g., applesauce, carrots, rice, or ice cream), or in breast milk or infant formula. Do not mix in other liquids. Administer within 15 minutes of opening the packet.
- Emphasize the importance of monitoring for neuropsychiatric symptoms and reporting them immediately to a healthcare provider.
- Consider the patient's overall asthma management plan; montelukast may be used as monotherapy or in combination with inhaled corticosteroids.
- For exercise-induced bronchoconstriction (EIB), a single dose can be taken at least 2 hours before exercise, but not more than once daily.
Alternative Therapies
- Inhaled corticosteroids (e.g., fluticasone, budesonide) for asthma
- Long-acting beta-agonists (LABAs) in combination with inhaled corticosteroids for asthma
- Short-acting beta-agonists (SABAs) for rescue relief in asthma
- Antihistamines (e.g., loratadine, cetirizine, fexofenadine) for allergic rhinitis
- Nasal corticosteroids (e.g., fluticasone nasal spray) for allergic rhinitis
- Cromolyn sodium (mast cell stabilizer)
- Omalizumab (anti-IgE antibody) for severe allergic asthma
- Zileuton (5-lipoxygenase inhibitor, another LTRA class)
Cost & Coverage
Average Cost:
Varies widely per packet
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (generic), Tier 3 (brand)
General Drug Facts
If your symptoms or health problems persist or worsen, it is essential to contact your doctor promptly. To ensure safe use, never share your medication with others, and do not take medication prescribed to someone else. This medication is accompanied by a Medication Guide, a patient fact sheet that provides important information. Please read this guide carefully and review it again whenever your prescription is refilled. If you have any questions or concerns about this medication, consult your doctor, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When reporting the incident, be prepared to provide details about the medication taken, the amount, and the time it occurred.