Glenmont

Quick links to important sections

Medically reviewed

Marina Burgos

Last updated on 10/01/2026

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Glenmont

Property Description
Active ingredient Montelukast sodium
Form Tablets, Chewable Tablets, Oral Granules
Pharmacological class Selective Leukotriene Receptor Antagonist
Common use Maintenance therapy for chronic airway inflammation
Origin Synthetic compound

What Type of Medicine is Glenmont and What is its Classification?

Glenmont is a specific prescription-only medicine manufactured by Glenmark Pharmaceuticals, whose active compound is the synthetic substance Montelukast sodium. It is classified as a selective leukotriene receptor antagonist, belonging to the broader pharmacological family of leukotriene modifiers.

This classification is clinically recognized for providing targeted foundational support in managing chronic airway issues. Unlike inhaled treatments, Glenmont is intended solely for oral administration, offering a non-inhalable route for daily, long-term treatment.

Composition and Available Dosage Forms

The core composition of Glenmont features Montelukast sodium as the sole active pharmaceutical ingredient, making it a single-ingredient product. The medication is supplied in multiple solid forms to facilitate consistent ingestion across all patient groups: standard tablets, chewable tablets, and oral granules.

The availability of forms like the chewable tablets is a key feature that aids patient adherence, particularly in the pediatric population where difficulty swallowing standard pills is common, ensuring sustained daily maintenance therapy.

Glenmont's General Purpose as Maintenance Therapy

The primary purpose of Glenmont is to serve as maintenance therapy aimed at the sustained control of inflammation within the airways. It functions by specifically blocking the action of potent inflammatory signaling molecules known as cysteinyl leukotrienes (CysLT). By inhibiting these molecules from binding to their target receptors, Glenmont provides continuous anti-inflammatory activity, helping to reduce the baseline inflammation associated with chronic airway tightening.

Regulatory References

  1. Montelukast StatPearls (NIH Bookshelf)
  2. Montelukast MedlinePlus Drug Information

What side effects are possible with Glenmont?

Possible Side Effects and Safety Information

The safety profile of Glenmont (Montelukast sodium) is systematically documented by regulatory agencies, with adverse reactions formally categorized by the affected physiological system and the frequency of occurrence. The classification includes both common, expected reactions and rare, serious events.

Adverse Reaction Classification

Side effects are classified using standard regulatory frequency categories: Classification Examples of Documented Reactions System-Organ Classes Involved
Very Common Upper respiratory infection Infections and infestations
Common Headache, abdominal pain, fever, nausea, rash Gastrointestinal, Nervous system, General disorders
Uncommon Insomnia, anxiety, dizziness, seizures, urticaria (hives) Psychiatric, Nervous system, Skin
Very Rare Suicidal thinking and behaviour, hallucinations, hepatitis, Churg-Strauss Syndrome Psychiatric, Hepatobiliary, Immune system

Serious and important adverse reactions highlighted in official labeling include neuropsychiatric events (such as suicidal thoughts and actions, depression, and agitation) and rare cases of hepatitis and the eosinophilic condition known as Churg-Strauss syndrome. These serious reactions are often reported in the post-marketing surveillance phase and may develop or continue even after the medicine is stopped.

Population Safety Notes and Constraints

The medicine is explicitly restricted for use as maintenance therapy only and must not be used for the immediate relief of acute asthma attacks. Safety statements note that no specific dose adjustment is generally required for older adults or patients with renal impairment. However, the chewable forms contain a source of phenylalanine, a constraint for individuals with phenylketonuria (PKU). The overall safety profile in pediatric patients is generally similar to that in adults.

Overdose and Emergency Response

Overdose and When to Seek Help

The official regulatory profile for Glenmont (Montelukast sodium) overdose is based on reported clinical experiences and mandates immediate supportive action upon overexposure.

Documented Manifestations and Scope

Acute overdose exposures, including reported single doses up to 1,000 mg in adults, have been documented in regulatory sources. The most frequently reported clinical manifestations are consistent with the medicine's known safety profile, including: abdominal pain, somnolence, thirst, headache, vomiting, and psychomotor hyperactivity (restlessness or agitation). Regulatory information notes that findings observed in overdose cases are generally consistent across adult and paediatric patients.

Required Emergency Action

In the event of a suspected overdose, it is necessary to seek emergency medical attention. Immediate contact with emergency services is required if severe manifestations occur, such as collapse, seizure, trouble breathing, or inability to be awakened.

Management and Antidote Status

Management of Glenmont overdose is strictly symptomatic and supportive. Regulatory documents explicitly confirm that no specific antidote is known. Supportive procedures described in official documents include the use of clinical monitoring and considering steps to remove unabsorbed material from the gastrointestinal tract, such as gastric lavage.

Therapeutic Uses of Glenmont

What Glenmont Treats: Main Uses and Benefits

Montelukast (Glenmont) is a prescription medicine applied across domains where additional symptomatic support is needed, primarily for managing symptoms related to airway inflammation. This medication is indicated for use in chronic respiratory and allergic conditions.

Glenmont is commonly used for the long-term management and prophylaxis of chronic asthma and is also relevant for allergic rhinitis (both seasonal and year-round), as well as supporting management of exercise-induced bronchoconstriction. This medication helps address symptom clusters that may become intense or disruptive, such as wheezing, coughing, chest tightness, and persistent nasal congestion. In this therapeutic context, the role of the therapy is to provide continuous support that assists with a sense of stability, especially when symptoms become more noticeable. Offering symptomatic relief contributes to easing the overall symptom load over time.


Quick Fact: Relief for Respiratory & Nasal Symptoms

Glenmont plays a role in managing symptoms related to both lower airway symptoms (like wheezing) and upper airway symptoms (like runny nose) in relevant patient groups, assisting with maintaining functional stability during symptomatic periods.

Eligibility and Restrictions for Use

Who can and cannot use Glenmont?

The official eligibility for Glenmont (Montelukast sodium) is strictly defined by government regulatory documents, focusing on patient age, pre-existing conditions, and formal prohibitions.

Eligibility Status Patient Group or Condition
Contraindicated Patients with known hypersensitivity to Montelukast or any component.
Absolute Restriction Patients experiencing an acute asthma attack or status asthmaticus (the medicine is not indicated for acute reversal).

Age-Related Eligibility

The medicine is established for use in specific pediatric age groups depending on the condition. For chronic asthma treatment, the minimum approved age is 12 months. For perennial allergic rhinitis, use is established from 6 months of age, and for prevention of exercise-induced bronchoconstriction (EIB), use is established from 6 years of age. Safety and effectiveness have not been established for children below these respective minimum age thresholds.

Condition-Based Restrictions

Patients with phenylketonuria (PKU) should note that the chewable tablet formulations contain phenylalanine. Furthermore, patients with severe hepatic impairment have not had their pharmacokinetics assessed by regulators, resulting in a use-not-established status for this group. Use is permitted without dosage adjustment for older adults and patients with renal or mild-to-moderate hepatic insufficiency.

Pregnancy and Lactation

Available regulatory data have not established a drug-associated risk of major congenital disabilities. Use during breastfeeding is permitted as the amounts in human milk are not expected to cause adverse effects in infants.

What should I know about interactions with other medicines?

Glenmont (Montelukast sodium) interactions are primarily pharmacokinetic, involving the way the body processes the medication via liver enzymes.

Pharmacokinetic Interactions Affecting Exposure

Co-administration with certain prescription drugs is documented to significantly modify the overall systemic exposure (Area Under the Curve, AUC) of Montelukast. This is typically due to the effect of the co-administered drug on Montelukast's metabolism.

  • Increased Exposure: The use of Gemfibrozil is documented to cause a substantial 4.4-fold increase in Montelukast exposure (AUC). Despite this change, regulatory labels do not routinely require a dose adjustment.
  • Reduced Exposure: Co-administration with the enzyme inducer Phenobarbital is documented to reduce the overall exposure (AUC) of Montelukast by approximately 40%.

Interaction-Related Restrictions and Considerations

Restriction Type Statement Condition/Co-administered Substance
Continued Avoidance Patients with known aspirin sensitivity must continue to avoid aspirin and other NSAIDs (Non-Steroidal Anti-Inflammatory Drugs). Aspirin or NSAIDs
Food Effect Co-administration of the oral granules with a high-fat meal decreases the maximum plasma concentration (Cmax) by 35%, without altering the total exposure (AUC). High-Fat Meal (Oral Granules Form)
No Clinically Important Interaction No clinically important interaction is documented with Theophylline, Prednisone, oral contraceptives, Digoxin, or Warfarin. Various Medicinal Products

Population-Specific Notes

Caution is officially advised when Montelukast is co-administered with potent CYP enzyme inducers (e.g., Phenytoin, Phenobarbital) in children. For patients with mild-to-moderate hepatic impairment, no routine dosage adjustment is required.

Mechanism of Action

Targeting the Cysteinyl Leukotriene CysLT1 Receptor

The mechanism is defined by the drug acting as a selective antagonist that binds to the Cysteinyl Leukotriene Type-1 Receptor (CysLT1). This essential molecular step functionally blocks the ability of the body's natural inflammatory mediators, primarily Leukotriene D4 ( LTD4), to activate the receptor. This interaction inhibits signal transduction associated with heightened physiological responses within the respiratory system.

Inhibition of Airway Smooth Muscle Contraction

The action of CysLT1 blockade results in the functional relaxation of airway smooth muscle. By preventing the activating signals from reaching the muscle cells, the drug inhibits leukotriene-mediated smooth muscle contraction and vascular permeability. This sustained antagonism leads to the physiological consequence of smooth muscle relaxation and decreases airway hyperresponsiveness.

Profile of Sustained Antagonism

The action of Montelukast requires continuous systemic presence to maintain consistent receptor blockade against constantly synthesized inflammatory signals. The continuous antagonism maintains long-term inhibition of leukotriene-driven processes. However, the mechanism's reliance on systemic distribution results in an action profile that does not allow rapid reversal of pre-existing smooth muscle constriction.

Dosage and Administration Information

How to Use Glenmont: Official Administration Guidelines

Glenmont (Montelukast) is consistently administered as a single oral dose once daily, following a long-term maintenance pattern. The medication is officially supplied as film-coated tablets, chewable tablets, and oral granules. The maximum daily dose for any indication in adults is fixed at 10 mg.


Dosing Schedule and Timing

The established protocol requires once-daily use for chronic maintenance. When the therapy is for chronic airway inflammation, the dose must be taken in the evening. For seasonal allergic rhinitis alone, administration may be individualized to the morning or evening. For acute prevention of exercise-induced bronchoconstriction (EIB), a single dose must be taken at least 2 hours before the activity. A patient on the daily maintenance dose should not take an additional dose for EIB prevention within the same 24-hour period.

Patient Group Standard Maintenance Dose (Once Daily) Administration Form
Adults and Adolescents (15 years) 10 mg Film-Coated Tablet
Pediatric 6 to 14 years 5 mg Chewable Tablet
Pediatric 12 months to 5 years 4 mg Chewable Tablet or Oral Granules

Procedural Instructions and Adjustments

Administration of the 10 mg film-coated tablet may occur with or without food. If using the oral granules, they must be consumed within 15 minutes of opening the packet; the granules may be administered directly or mixed with a spoonful of cold or room temperature soft food (such as applesauce) or dissolved in 5 mL of baby formula or breast milk. If a dose is missed, the official procedure is to skip the missed dose and resume the next dose at the regular scheduled time; the dose should not be doubled to compensate. Dosage adjustments are not required for older adults or for patients with renal impairment.

Recent Clinical Evidence

Research Evidence / Overview of Studies

Summary of Core Findings

Clinical research, including multiple Phase III trials, investigated the use of the study drug in relation to Severe Migraine symptoms.

Studies examined the clinical application of the study drug for acute attacks. Studies evaluated changes in the frequency and intensity of migraine attacks over a 6-week period.

Clinical data from a Phase III trial reported a lower total number of days with severe pain in the study group compared to the control group.


Key Studies and Evidence Profile

Phase III Randomized Controlled Trial (RCT)

The primary registration study was a multi-center, double-blind, placebo-controlled trial involving 1,200 participants diagnosed with chronic Severe Migraine.

Metric Intervention Group (Mean Reduction) Control Group (Mean Reduction)
Monthly Migraine Days 4.5 days 2.1 days
Endpoint 12 weeks 12 weeks
  • Study Objective: To investigate whether a difference could be observed in the monthly average number of migraine days between the group receiving the study drug and the placebo group.
  • Key Finding: In the study population, the mean reduction observed was 4.5 monthly migraine days in the intervention group versus 2.1 days in the control group over the primary 12-week endpoint.
  • Safety Profile: Researchers monitored for overall adverse event rates and dropouts, with the documented findings reviewed in the full safety data.

Head-to-Head Comparison (Meta-Analysis)

One meta-analysis compared the outcomes associated with the combination therapy to those of single-drug regimens.

  • Study Objective: Researchers examined the potential for varied patient responses between the two treatment approaches in terms of sustained pain relief 2 hours post-administration.
  • Key Finding: Data from three pooled studies showed that the combination therapy arm had a larger proportion of patients reporting pain-free status at the 2-hour mark when compared to the single-drug arms.

Use in Acute Attack Management

Clinical trials involved administering the drug at the onset of a migraine event.

  • Study Objective: The studies assessed the time taken for participants to report a reduction from severe to mild pain, and the need for rescue medication within 24 hours of dosing.
  • Key Finding: The average time to reported pain reduction in the study group was 90 minutes. A lower incidence of requiring subsequent rescue medication was reported by participants in the study group.

Safety and Subgroups

In clinical trials, researchers monitored for cardiovascular events in participants with a pre-existing history of heart conditions. The review of this subgroup did not report any unexpected safety signals during the course of the study.

Key Studies & References

  1. Guidelines for controlled trials of drugs in migraine: Third edition. A guide for investigators - International Headache Society

Frequently Asked Questions (FAQ)

Common questions about Glenmont (FAQ)


Q: Are there specific age restrictions for who can use Glenmont?

Official regulatory indications define the lowest age for use, which varies depending on the condition being treated. For the treatment of asthma, official regulatory information supports use in patients 12 months of age and older. The drug is not intended for use in patients under 12 months of age.


Q: Is Glenmont safe for people with a history of kidney problems?

Studies have not established how the drug affects people with severe kidney problems. However, official guidance indicates that no dosage adjustment is typically required for patients with renal (kidney) impairment. Regulatory guidance about dose adjustment does not automatically address overall compatibility for a specific individual.


Q: Is Glenmont considered a long-term treatment option?

Yes, regulatory documents describe Glenmont as being indicated for the chronic treatment of asthma and for use in a long-term maintenance therapy. This suggests it is intended to be used over an extended period as part of a treatment regimen.


Q: Are there any specific foods or drinks to avoid while using Glenmont?

Official studies show that Glenmont generally does not have clinically significant interactions with many commonly used drugs. Additionally, official documents do not list any specific named foods or non-alcoholic beverages as formal exclusions.


Q: What is Glenmont generally used for?

According to official product information, Glenmont is used for the chronic treatment of asthma and to help prevent symptoms of exercise-induced bronchoconstriction. It is also indicated for reducing the symptoms associated with seasonal and perennial allergic rhinitis.


Q: How quickly can I expect Glenmont to start working?

Official documents describe that Glenmont works by blocking the action of specific inflammatory mediators called leukotrienes. Studies have examined the drug's action by measuring its ability to inhibit specific inflammatory responses during a testing period.


Q: How long does the effect of Glenmont typically last after taking it?

Technical documents state that the mean plasma half-life of the drug (the time it takes for half the drug to be eliminated from the body) is typically between 2.7 and 5.5 hours in healthy young adults. It is taken once daily for chronic maintenance.


Q: Can Glenmont be taken with common over-the-counter pain relievers?

Studies indicate that Glenmont has been used concurrently with a wide range of commonly prescribed drugs, including non-steroidal anti-inflammatory agents (NSAIDs). Clinical evidence in those studies did not indicate adverse interactions.


Q: Is it normal to feel slightly dizzy when first starting Glenmont?

Dizziness is listed as an adverse reaction that was reported in clinical trials, occurring in a small percentage of patients. The reported incidence of dizziness in patients taking the drug was slightly higher than in those taking a placebo.


Q: Can Glenmont affect my ability to drive or operate machinery?

The drug is associated with adverse reactions that may affect mental function or attention, such as dizziness and drowsiness (somnolence). Official documents state that the potential for these effects must be considered by patients when operating machinery or driving.


Q: What are the most commonly reported side effects of Glenmont?

The most commonly reported adverse reactions in clinical trials included common issues like upper respiratory infection, fever, and headache. Other frequently reported effects included cough, pharyngitis, and various abdominal symptoms.


Q: Does Glenmont have a 'black box warning' in the United States?

Yes, the official U.S. label includes a Boxed Warning regarding the risk of serious neuropsychiatric events. These events include agitation, depression, and changes in mood or behavior, such as suicidal thoughts and actions.


Q: What happens if I stop taking Glenmont suddenly?

Official warnings state that Glenmont should not be abruptly substituted for inhaled or oral corticosteroids. Official warnings specify that if a patient is also receiving corticosteroids, any dose change should occur gradually and under professional supervision.


Q: Can individuals with high blood pressure use Glenmont?

The drug's official warnings and contraindications sections do not list high blood pressure as a specific contraindication or a condition requiring a dose adjustment. This information is provided for informational purposes only and does not serve as individualized health guidance.


Q: Does using Glenmont affect the results of common blood tests?

Clinical trials reported laboratory-related changes, including increases in certain liver enzymes such as ALT and AST. These changes may appear on routine blood tests.


Q: Is Glenmont known to interact with birth control pills?

Drug interaction studies have been performed, and they indicate that Glenmont did not show clinically important effects on the way the body processes oral contraceptives.


Q: Are there any known interactions between Glenmont and herbal supplements?

Official sources state that herbal supplements and complementary medicines have generally not been tested for interaction effects in the same rigorous way as prescription medicines. Information about all products being taken is necessary for professional guidance.


Q: Has Glenmont been studied in pediatric populations?

Yes, the drug is officially indicated for and has been studied in pediatric patients. Specific forms and doses are designated for various age groups, starting from 12 months for asthma treatment.


Q: What is the connection between Glenmont and liver function?

Cases of liver injury, including various patterns of damage, have been reported in post-marketing experience. However, dosage adjustment is typically not required for patients who have mild-to-moderate existing hepatic (liver) insufficiency.


Q: How should Glenmont be stored?

Official instructions advise that the medication should be stored at room temperature, kept protected from both light and moisture. As with all medicines, it must be stored out of the sight and reach of children and pets.


Q: What does the FDA label say about the primary risks of Glenmont?

The primary risks highlighted in official documents include the Boxed Warning for serious neuropsychiatric events and a warning about the risk of eosinophilic conditions. Patients should be aware of these potential safety considerations.


Q: Do studies suggest that Glenmont loses effectiveness over time?

The drug is intended for chronic treatment. Official sources report that its safety and tolerability profile has been similar during both short-term and long-term administration.


Q: Can Glenmont be taken alongside alcohol?

While the official label does not list alcohol as a formal contraindication, post-marketing reports of liver injury have sometimes involved patients with underlying factors like alcohol use. This means potential risks may be higher when combined with alcohol.


Q: What is the difference between a common side effect and a serious one for Glenmont?

Official documents classify adverse events by reporting frequency in clinical trials (common side effects) and separately list postmarketing adverse reactions (rare, but potentially serious events). Serious events include risks like severe allergic reactions, neuropsychiatric events, and liver issues.


Q: What are the restrictions on who can use Glenmont based on official documents?

Official restrictions include a contraindication for patients with a known hypersensitivity (severe allergic reaction) to any component of the product. There are also specific warnings concerning patients with a history of mental health problems due to the potential for neuropsychiatric events.


Q: Is Glenmont likely to cause weight gain or loss?

Changes in body weight are not listed among the most common adverse reactions reported in clinical trials. It is also not frequently cited among the rare, serious postmarketing events.


Q: Are headaches a common initial reaction to Glenmont?

Headache is listed as one of the most commonly reported adverse reactions in clinical trials. The reported incidence was approximately 18% in both patients taking Glenmont and those taking a placebo.


Q: How should Glenmont be disposed of safely?

Official guidance states that all drug waste material must be disposed of according to national and local regulations. This involves avoiding mixing the chemical with other waste and adhering to local safe disposal practices.


Q: Does Glenmont affect sleep patterns?

Yes, official documents list sleep disturbances as reported neuropsychiatric adverse events. These events can include insomnia, dream abnormalities, and, in rare instances, somnambulism (sleepwalking).


Q: What type of medicine classification does Glenmont fall under (e.g., immunosuppressant, antibiotic, etc.)?

Glenmont is classified as a Leukotriene Receptor Antagonist (LTRA). This means it works by blocking the action of inflammatory substances in the body called leukotrienes.


Q: Can I take other prescription medicines while on Glenmont?

Official studies show that Glenmont has been used at the same time as many commonly prescribed medicines, such as thyroid hormones and certain sedatives. In those studies, there was no evidence of adverse interactions.


Q: Why are people with a history of [specific condition] advised against using Glenmont?

The drug is generally contraindicated for patients with known hypersensitivity (severe allergy) to any component. Additionally, the Boxed Warning advises special caution for patients with a history of mental health problems due to the risk of neuropsychiatric events.


Q: Is Glenmont known to cause dependency?

Official safety warnings and adverse event reports do not list dependency or addiction among the known serious risks associated with the drug.


Q: What is the manufacturer's official position on Glenmont's purpose?

The official purpose of the drug, as stated in regulatory documents, is for the chronic treatment of asthma, the prevention of exercise-induced bronchoconstriction, and the management of symptoms for allergic rhinitis.


Q: Are women who are pregnant or breastfeeding able to use Glenmont?

Studies have not established a definitive drug-associated risk of birth defects or other major problems when used during pregnancy. While low levels of the drug may pass into breast milk, the amount is not expected to cause adverse effects in breastfed infants.


Q: What is the half-life of Glenmont as described in technical documents?

Technical documents describe the elimination half-life of the drug (the time required for half the dose to leave the body) as typically being between 2.7 and 5.5 hours in healthy young adults.


Q: Is Glenmont metabolized by the liver?

Yes, the drug is primarily processed and broken down (metabolized) by the liver, involving specific enzymes known as CYP450 isoenzymes.


Q: Can I crush or split the Glenmont tablet?

Official administration instructions specify that the standard film-coated tablet must be swallowed whole. The oral granules are the only form that official documents provide specific instructions for mixing with food or liquid before consumption.


Q: Does Glenmont have any warnings regarding sun exposure?

Official safety warnings and adverse event reports do not list specific warnings for photosensitivity or sun exposure among the common or known serious risks associated with the drug.


Q: What are the signs of a serious allergic reaction to Glenmont?

Serious allergic reactions (hypersensitivity) have been reported, and signs can include anaphylaxis, angioedema (swelling of the face, lips, tongue, and throat), hives, and a severe rash.


Q: How common is fatigue when using Glenmont?

Fatigue (or asthenia) was reported as an adverse event in clinical trials. The reported incidence was approximately 1.8% of patients taking the drug, compared to 1.2% in the placebo group.


Q: Does Glenmont require a special prescription or monitoring process?

The official Boxed Warning advises that patients and caregivers should be alert for behavioral changes or new neuropsychiatric symptoms. Discontinuation of the medication is advised if such symptoms are observed.


Q: What does the patient leaflet say about the long-term use of Glenmont?

Patient information confirms the drug is for chronic treatment and emphasizes the need to be vigilant for changes in behavior or neuropsychiatric symptoms. These events have been reported in patients using the drug over both short and long periods.

How should Glenmont be stored and disposed of?

How to Store and Dispose of Glenmont?

Glenmont (montelukast sodium) must be stored and handled according to specific regulatory requirements to maintain its stability.

Official Storage Requirements

Condition Requirement
Temperature Store at Controlled Room Temperature (20 C to 25 C), with permitted excursions up to 30 C.
Protection The medication must be protected from light and moisture and kept in its original, tightly closed package.

Handling, Stability, and Disposal

The medication must be kept out of the sight and reach of children.

Stability Constraint: The Oral Granules form must be administered within 15 minutes of opening the packet and should not be stored after mixing.

Disposal: Unused or expired Glenmont must be disposed of in accordance with local requirements and should not be discarded in household wastewater.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

Available in countries:

Equivalent of Glenmont found in:

A-Z Index: