Singulair 4mg Chewable Tablets
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
B
FDA Approved
Feb 1998
DEA Schedule
Not Controlled
Overview
What is this medicine?
Montelukast is a medicine used to prevent and treat asthma symptoms and to relieve symptoms of seasonal allergies (hay fever). It works by blocking natural substances in your body called leukotrienes, which can cause inflammation and narrowing of the airways in your lungs, and allergy symptoms like sneezing and runny nose. This 4mg chewable tablet is specifically for children aged 2 to 5 years.
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 prescription and follow the instructions closely. You can take this medication with or without food. Be sure to chew the medication thoroughly before swallowing.
It's essential to continue taking this medication even when you're not experiencing symptoms. If you're taking this medication to prevent exercise-induced breathing problems, take it at least 2 hours before exercising. For asthma management, take your medication in the evening as directed.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, away from light and moisture. Keep it in a dry place, avoiding storage in a bathroom. Store your medication in its original container to preserve its quality.
What to Do If You Miss a Dose
If you miss a dose, skip it and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. You can take this medication with or without food. Be sure to chew the medication thoroughly before swallowing.
It's essential to continue taking this medication even when you're not experiencing symptoms. If you're taking this medication to prevent exercise-induced breathing problems, take it at least 2 hours before exercising. For asthma management, take your medication in the evening as directed.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, away from light and moisture. Keep it in a dry place, avoiding storage in a bathroom. Store your medication in its original container to preserve its quality.
What to Do If You Miss a Dose
If you miss a dose, skip it and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Take montelukast once daily in the evening, even if you feel well. Consistency is key for its effectiveness.
- This medication is not for treating sudden asthma attacks. Always carry your rescue inhaler (e.g., albuterol) for acute symptoms.
- Chew the tablet completely before swallowing. Do not swallow whole.
- Continue to use other asthma medications as prescribed by your doctor unless instructed otherwise.
- Be aware of and report any changes in mood or behavior, including agitation, aggression, depression, or sleep problems, to your doctor immediately.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Not applicable for 4mg chewable tablets (typically 10mg tablet for adults)
Condition-Specific Dosing:
asthma_or_seasonal_allergic_rhinitis:
10 mg orally once daily in the evening (for adults and adolescents âĨ15 years)
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established (safety and efficacy not established in patients younger than 6 months of age)
Child:
4 mg chewable tablet orally once daily in the evening for patients 2 to 5 years of age for asthma or seasonal allergic rhinitis. 5 mg chewable tablet orally once daily in the evening for patients 6 to 14 years of age for asthma or seasonal allergic rhinitis.
Adolescent:
Not applicable for 4mg chewable tablets (typically 10mg tablet for adolescents âĨ15 years)
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 significantly 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, LPE4) are potent inflammatory eicosanoids released from various cells, including mast cells and eosinophils. These leukotrienes bind to CysLT1 receptors in the airways and on other pro-inflammatory cells, causing bronchoconstriction, mucus secretion, vascular permeability, and eosinophil recruitment. Montelukast blocks the action of LTD4 at the CysLT1 receptor, thereby inhibiting these effects and improving asthma and allergic rhinitis symptoms.
Pharmacokinetics
Absorption:
Bioavailability:
64% (for 10mg tablet)
Tmax:
2-4 hours (for 10mg tablet); 2-2.5 hours (for 4mg chewable)
FoodEffect:
Food decreases Cmax by 35% and AUC by 21% for the 10mg tablet, but this is not considered clinically significant. For the 4mg chewable tablet, food does not significantly affect bioavailability.
Distribution:
Vd:
8-11 liters
ProteinBinding:
>99%
CnssPenetration:
Limited
Elimination:
HalfLife:
2.7-5.5 hours
Clearance:
Not readily available as a specific rate, but primarily hepatic clearance.
ExcretionRoute:
Feces (approximately 86%), Urine (approximately 14%)
Unchanged:
<0.2% in urine
Pharmacodynamics
OnsetOfAction:
Within 1 day (for asthma symptom improvement)
PeakEffect:
Variable, sustained over 24 hours with once-daily dosing
DurationOfAction:
24 hours
Safety & Warnings
BLACK BOX WARNING
Serious neuropsychiatric events have been reported with the use of montelukast. The benefits of montelukast may not outweigh the risks in some patients, particularly when the symptoms of the disease are mild and can be adequately treated with other therapies. Discontinue montelukast if neuropsychiatric changes occur.
Side Effects
Serious Side Effects: Seek Medical Help Immediately
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention right away:
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 do not experience any side effects or only have mild ones. If you are bothered by any of the following side effects or if they do not go away, contact your doctor or seek medical help:
Headache
Stomach pain or diarrhea
Signs of a common cold
Cough
Note: This is not an exhaustive list of possible 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.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention right away:
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 do not experience any side effects or only have mild ones. If you are bothered by any of the following side effects or if they do not go away, contact your doctor or seek medical help:
Headache
Stomach pain or diarrhea
Signs of a common cold
Cough
Note: This is not an exhaustive list of possible 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., anxiety, depression, suicidal thoughts, aggression, agitation, hallucinations, sleep disturbances, unusual dreams, memory problems, tremors, obsessive-compulsive symptoms)
- Signs of liver problems (e.g., yellowing of skin/eyes, dark urine, severe stomach pain, unusual tiredness)
- Allergic reactions (e.g., rash, itching, swelling, severe dizziness, trouble breathing)
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.
* Any existing health problems, as this medication may interact with certain conditions.
To ensure your safety, it is crucial to verify that this medication can be taken with all your current medications and health conditions. Never start, stop, or adjust the dose 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.
* Any existing health problems, as this medication may interact with certain conditions.
To ensure your safety, it is crucial to verify that this medication can be taken with all your current medications and health conditions. Never start, stop, or adjust the dose of any medication without first consulting your doctor.
Precautions & Cautions
Important Warnings and Cautions
General Information
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you have phenylketonuria (PKU), consult with your doctor, as some products contain phenylalanine. Additionally, if you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks with your doctor to ensure the best decision for you and your baby.
Breathing Problems
If you experience worsening breathing problems, or if your rescue inhaler becomes less effective or is needed 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 experience worsening symptoms when taking aspirin, avoid aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen while using this medication.
Special Considerations
If you are switching to this medication from a steroid, do not abruptly stop taking the steroid. Instead, consult with your doctor to gradually taper the steroid dose and minimize potential side effects.
General Information
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you have phenylketonuria (PKU), consult with your doctor, as some products contain phenylalanine. Additionally, if you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks with your doctor to ensure the best decision for you and your baby.
Breathing Problems
If you experience worsening breathing problems, or if your rescue inhaler becomes less effective or is needed 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 experience worsening symptoms when taking aspirin, avoid aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen while using this medication.
Special Considerations
If you are switching to this medication from a steroid, do not abruptly stop taking the steroid. Instead, consult with your doctor to gradually taper the steroid dose and minimize potential side effects.
Overdose Information
Overdose Symptoms:
- Abdominal pain
- Somnolence (drowsiness)
- Thirst
- Headache
- Vomiting
- Psychomotor hyperactivity
What to Do:
There is no specific antidote. Treatment is symptomatic and supportive. Contact a poison control center or emergency services immediately. Call 1-800-222-1222.
Drug Interactions
Moderate Interactions
- Phenobarbital (may decrease montelukast AUC by approximately 40%)
- Rifampin (may decrease montelukast AUC by approximately 40%)
Monitoring
Baseline Monitoring
Liver function tests (LFTs)
Rationale: Although rare, hepatic events have been reported. Baseline assessment can be considered, especially in patients with pre-existing liver disease.
Timing: Prior to initiation, if clinically indicated.
Routine Monitoring
Asthma/Allergy symptom control
Frequency: Regularly (e.g., at follow-up visits)
Target: Improved symptom scores, reduced rescue inhaler use, improved quality of life.
Action Threshold: Persistent or worsening symptoms may indicate need for dose adjustment or alternative therapy.
Neuropsychiatric symptoms (e.g., agitation, aggression, depression, sleep disturbances, suicidal thoughts/behavior)
Frequency: Ongoing, at each visit and through patient/caregiver education
Target: Absence of new or worsening neuropsychiatric symptoms.
Action Threshold: If symptoms occur, discontinue montelukast and assess risk/benefit. Consider alternative therapy.
Symptom Monitoring
- Wheezing
- Shortness of breath
- Cough
- Chest tightness
- Nasal congestion
- Sneezing
- Runny nose
- Itchy eyes
- Mood changes
- Agitation
- Aggression
- Anxiety
- Depression
- Disorientation
- Disturbance in attention
- Dream abnormalities
- Hallucinations
- Insomnia
- Irritability
- Memory impairment
- Obsessive-compulsive symptoms
- Restlessness
- Somnambulism (sleepwalking)
- Suicidal thoughts and behavior
- Tremor
- Unusual changes in behavior
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 only if clearly needed.
Trimester-Specific Risks:
First Trimester:
No increased risk of major birth defects observed in human studies, but data are limited.
Second Trimester:
No specific risks identified.
Third Trimester:
No specific risks identified.
Lactation
Montelukast is excreted in breast milk. The amount is small, and adverse effects in breastfed infants are not expected. However, caution should be exercised when montelukast is administered to a nursing mother.
Infant Risk:
L3 (Moderately Safe) - Monitor infant for potential adverse effects (e.g., irritability, poor feeding, rash), though unlikely.
Pediatric Use
Montelukast 4mg chewable tablets are specifically approved and dosed for children 2 to 5 years of age. Safety and efficacy have not been established in children younger than 6 months of age. Close monitoring for neuropsychiatric events is crucial in pediatric patients.
Geriatric Use
No dosage adjustment is generally required in elderly patients. Clinical studies did not identify differences in safety or effectiveness between elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.
Clinical Information
Clinical Pearls
- Montelukast is a maintenance therapy and should not be used for acute asthma attacks. Patients should always have a rescue inhaler available.
- Administer once daily in the evening for asthma or seasonal allergic rhinitis. For exercise-induced bronchoconstriction, take at least 2 hours before exercise, but do not take additional doses within 24 hours.
- Counsel patients and caregivers extensively on the potential for neuropsychiatric side effects, including mood changes, agitation, depression, and suicidal thoughts. Emphasize immediate reporting of such symptoms and consideration of discontinuation.
- Chewable tablets must be chewed completely before swallowing. Do not swallow whole.
- Montelukast can be taken with or without food.
Alternative Therapies
- Inhaled corticosteroids (e.g., fluticasone, budesonide) - often first-line for persistent asthma.
- Long-acting beta-agonists (LABAs) - often used in combination with ICS for asthma.
- Short-acting beta-agonists (SABAs) - for rescue relief of asthma symptoms.
- Other leukotriene receptor antagonists (e.g., zafirlukast) - less commonly used.
- Mast cell stabilizers (e.g., cromolyn) - for asthma prevention.
- Oral antihistamines (e.g., loratadine, cetirizine) - for allergic rhinitis.
- Nasal corticosteroids (e.g., fluticasone nasal spray) - for allergic rhinitis.
Cost & Coverage
Average Cost:
Varies widely, typically $10-$50 per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (for generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor promptly. To ensure your safety, never share your medication with others or take someone else's medication. This medication is accompanied by a Medication Guide, which provides crucial information. Please read this guide carefully and review it again whenever you receive a refill. If you have any questions or concerns about this medication, don't hesitate to consult with 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 quantity, and the time it occurred.