Singulair 10mg 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
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, including those caused by exercise, and to relieve symptoms of seasonal and year-round allergies. It works by blocking natural substances in your body called leukotrienes, which can cause inflammation and narrowing of airways in your lungs, and allergy symptoms.
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. It's essential to continue taking this medication even when you're not experiencing symptoms.
If you're taking this medication to prevent breathing problems that occur with exercise, be sure to take it at least 2 hours before physical activity. If you're using this medication to manage asthma, take it in the evening as directed.
Storing and Disposing of Your Medication
To maintain the quality and effectiveness of your medication, store it at room temperature, protected from light. Keep it in a dry place, avoiding storage in a bathroom. Store your medication in its original container to preserve its potency.
What to Do If You Miss a Dose
If you miss a dose, skip it and return to your regular 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. It's essential to continue taking this medication even when you're not experiencing symptoms.
If you're taking this medication to prevent breathing problems that occur with exercise, be sure to take it at least 2 hours before physical activity. If you're using this medication to manage asthma, take it in the evening as directed.
Storing and Disposing of Your Medication
To maintain the quality and effectiveness of your medication, store it at room temperature, protected from light. Keep it in a dry place, avoiding storage in a bathroom. Store your medication in its original container to preserve its potency.
What to Do If You Miss a Dose
If you miss a dose, skip it and return to your regular 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. For exercise-induced bronchoconstriction, take at least 2 hours before exercise, but do not take another dose within 24 hours.
- Montelukast is NOT for treating sudden asthma attacks. Always carry your rescue inhaler (e.g., albuterol) for acute attacks.
- Continue to use your other asthma medications (e.g., inhaled corticosteroids) as prescribed, unless your doctor tells you otherwise.
- Avoid known asthma triggers (e.g., allergens, smoke, cold air).
- Maintain a healthy lifestyle, including regular exercise (if medically appropriate) and a balanced diet.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
10 mg orally once daily in the evening
Dose Range:
10 - 10 mg
Condition-Specific Dosing:
asthma:
10 mg orally once daily in the evening
allergicRhinitis:
10 mg orally once daily in the evening
exerciseInducedBronchoconstriction:
10 mg orally at least 2 hours before exercise, not to be taken more than once daily
Pediatric Dosing
Neonatal:
Not established
Infant:
6 months to 5 years: 4 mg chewable tablet or oral granules once daily in the evening
Child:
6 to 14 years: 5 mg chewable tablet once daily in the evening
Adolescent:
15 years and older: 10 mg 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. Montelukast is extensively metabolized by the liver.
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, LTE4) are potent inflammatory eicosanoids released from various cells, including mast cells and eosinophils. These mediators bind to CysLT1 receptors, leading to bronchoconstriction, mucus secretion, vascular permeability, and eosinophil recruitment, all of which contribute to the pathophysiology of asthma and allergic rhinitis. Montelukast blocks the binding of CysLTs to the CysLT1 receptor, thereby inhibiting these effects.
Pharmacokinetics
Absorption:
Bioavailability:
64% (10 mg tablet)
Tmax:
3-4 hours (10 mg tablet)
FoodEffect:
Food does not significantly affect the bioavailability of the 10 mg tablet. For 4 mg and 5 mg chewable tablets, food may decrease Cmax but does not affect AUC.
Distribution:
Vd:
8-11 L
ProteinBinding:
>99%
CnssPenetration:
Limited
Elimination:
HalfLife:
2.7-5.5 hours
Clearance:
Not available (primarily hepatic metabolism)
ExcretionRoute:
Fecal (86%), Renal (<0.2%)
Unchanged:
<0.2%
Pharmacodynamics
OnsetOfAction:
Within 1 day for asthma symptom improvement; within 2 hours for exercise-induced bronchoconstriction prevention.
PeakEffect:
FEV1 improvement within 2 weeks of initiation; maximal effect for exercise-induced bronchoconstriction prevention within 2 hours.
DurationOfAction:
24 hours (allows for once-daily dosing)
Safety & Warnings
BLACK BOX WARNING
Serious neuropsychiatric events have been reported with the use of montelukast. These postmarketing reports include agitation, aggression, depression, sleep disturbances, tremor, suicidal thoughts and behavior (including suicide). Because of the risk of neuropsychiatric events, 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
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, contact 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
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, contact 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 or increased need for rescue inhaler
- New or worsening mood changes (e.g., agitation, aggression, anxiety, depression, irritability)
- Sleep disturbances (e.g., nightmares, insomnia)
- Behavioral changes (e.g., restlessness, tremor)
- Suicidal thoughts or actions
- Signs of an allergic reaction (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 it is safe to take this medication with all your current medications and health conditions. Never start, stop, or change 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.
* 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 change the dosage of any medication without first consulting your doctor.
Precautions & Cautions
Important Information About This 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, a decrease in the effectiveness of your rescue inhaler, or an increased need to use your rescue inhaler, 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, it is recommended that you avoid aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, while taking this medication.
Transitioning from Steroid Medication
If you are switching to this medication from a steroid, do not abruptly stop taking the steroid. Instead, your doctor may need to gradually reduce the steroid dosage to minimize potential side effects. It is essential to consult with your doctor to determine the best course of action.
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, a decrease in the effectiveness of your rescue inhaler, or an increased need to use your rescue inhaler, 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, it is recommended that you avoid aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, while taking this medication.
Transitioning from Steroid Medication
If you are switching to this medication from a steroid, do not abruptly stop taking the steroid. Instead, your doctor may need to gradually reduce the steroid dosage to minimize potential side effects. It is essential to consult with your doctor to determine the best course of action.
Overdose Information
Overdose Symptoms:
- Abdominal pain
- Somnolence (drowsiness)
- Thirst
- Headache
- Vomiting
- Psychomotor hyperactivity
What to Do:
Seek immediate medical attention or call Poison Control at 1-800-222-1222. There is no specific antidote; treatment is supportive.
Drug Interactions
Moderate Interactions
- Phenobarbital
- Rifampin
- Gemfibrozil
Monitoring
Baseline Monitoring
Pulmonary Function Tests (e.g., FEV1)
Rationale: To establish baseline lung function for asthma control assessment.
Timing: Prior to initiation of therapy
Asthma/Allergy Symptom Score
Rationale: To establish baseline symptom severity.
Timing: Prior to initiation of therapy
Routine Monitoring
Asthma/Allergy Symptom Control
Frequency: Regularly (e.g., monthly or as clinically indicated)
Target: Improved symptom control, reduced rescue inhaler use, improved quality of life
Action Threshold: Worsening symptoms, increased rescue inhaler use, or lack of improvement may indicate need for re-evaluation or alternative therapy.
Neuropsychiatric Symptoms
Frequency: Ongoing, at each visit
Target: Absence of new or worsening behavioral changes, agitation, aggression, depression, suicidal ideation/behavior.
Action Threshold: Any new or worsening neuropsychiatric symptoms warrant immediate discontinuation and medical evaluation.
Symptom Monitoring
- Asthma symptoms (wheezing, shortness of breath, cough, chest tightness)
- Allergic rhinitis symptoms (sneezing, runny nose, nasal congestion, itching)
- Mood changes (agitation, aggression, anxiety, depression, irritability)
- Sleep disturbances (insomnia, nightmares)
- Behavioral changes (restlessness, tremor)
- Suicidal thoughts or actions
Special Patient Groups
Pregnancy
Montelukast is Pregnancy Category B. Studies in animals have shown no evidence of 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 benefits outweigh the potential risks.
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 into human breast milk. The amount is very small, and adverse effects on the breastfed infant are unlikely. However, monitor the infant for potential adverse effects such as irritability or rash. Use with caution.
Infant Risk:
L3 (Moderately safe; monitor infant for potential adverse effects)
Pediatric Use
Approved for use in children as young as 6 months of age. Dosing is weight/age-dependent. Neuropsychiatric events, including suicidal ideation, have been reported in pediatric patients; careful monitoring is essential.
Geriatric Use
No dosage adjustment is generally required in elderly patients. The safety and efficacy profile is similar to that in younger adults. However, elderly patients may be more sensitive to drug effects and should be monitored for adverse reactions.
Clinical Information
Clinical Pearls
- Montelukast is a maintenance medication and should not be used for acute asthma attacks. Patients should always have a rescue inhaler available.
- Emphasize the importance of taking the medication consistently every evening, even when symptoms are controlled.
- Educate patients and caregivers about the potential for neuropsychiatric side effects (e.g., mood changes, aggression, suicidal thoughts) and instruct them to report any such symptoms immediately to their healthcare provider. Discontinuation may be necessary.
- While generally well-tolerated, some patients may experience headache, abdominal pain, or upper respiratory infection symptoms.
- Montelukast can be used as monotherapy for mild persistent asthma or as add-on therapy for moderate to severe persistent asthma not adequately controlled by inhaled corticosteroids.
Alternative Therapies
- Inhaled Corticosteroids (e.g., fluticasone, budesonide) - cornerstone of asthma management
- Long-Acting Beta-Agonists (LABAs) (e.g., salmeterol, formoterol) - often combined with ICS
- Short-Acting Beta-Agonists (SABAs) (e.g., albuterol) - for rescue relief
- Other Leukotriene Modifiers (e.g., zafirlukast, zileuton - less commonly used due to side effects/dosing)
- Cromolyn sodium (mast cell stabilizer)
- Omalizumab (Xolair) - anti-IgE monoclonal antibody for severe allergic asthma
- Mepolizumab, Reslizumab, Benralizumab (anti-IL-5 biologics) - for severe eosinophilic asthma
- Dupilumab (anti-IL-4/IL-13 biologic)
Cost & Coverage
Average Cost:
Varies widely, typically $10-$50 for generic per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (Generic)
General Drug Facts
If your symptoms or health issues 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, which provides crucial information for patients. Please read this guide carefully and review it again whenever you receive a refill of this medication. If you have any questions or concerns about this medication, 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 seeking help, be prepared to provide details about the overdose, including the substance taken, the amount, and the time it occurred.