Asmakast

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Medically reviewed

Rosario Oropesa

Last updated on 22/12/2025

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 Asmakast

Property Description
Active ingredient Montelukast (as Montelukast sodium)
Form Oral tablet (film-coated, chewable) and oral granules
Pharmacological class Leukotriene Receptor Antagonist (LTRA)
General purpose Management of chronic airway inflammation
Origin Synthetic

What is Asmakast and What is its Active Composition?

Asmakast is a specific trade name for a medication whose sole active component is the highly selective, synthetic chemical entity Montelukast (specifically, Montelukast sodium). It is strictly a prescription-only (Rx-only) medication. Asmakast is supplied for oral use, primarily available in formulations such as the film-coated tablet, the chewable tablet, and oral granules, positioning it as an accessible option for different age groups. The composition is a single-entity product intended for systemic absorption, meaning it works throughout the body for long-term control rather than rapid, localized relief.

Asmakast's Classification: A Leukotriene Receptor Antagonist

This medication is pharmacologically defined as a Leukotriene Receptor Antagonist (LTRA), a classification that places it within the established group of Antiasthmatic Agents. LTRAs, unlike antihistamines or traditional inhaled agents, function by targeting a specific biochemical pathway: selectively binding to the CysLT1 receptor to block the inflammatory effects of chemical messengers such as leukotriene D4 (LTD4). This specific action is widely clinically recognized for its efficacy in controlling the underlying inflammatory drivers of chronic airway disease.

General Purpose: Why is this Type of Medicine Used?

The general therapeutic purpose of this LTRA medication is to provide sustained support by disrupting the chronic inflammatory cascade that contributes to airway hyperactivity. By inhibiting leukotriene action, Montelukast assists in the reduction of swelling and muscle contraction within the airways. This action, which is supported by global regulatory approvals, helps maintain more open airways and stabilize respiratory function. The convenient oral formulation often directs its use toward consistent, long-term management in patients requiring maintenance therapy.

Regulatory References

  1. Montelukast: MedlinePlus Drug Information

What side effects are possible with Asmakast?

Possible side effects and safety information

The safety profile for Montelukast (Asmakast) is established through regulatory classification, with adverse reactions grouped by frequency and affected body system as documented in official government sources (e.g., EMA and FDA). This information is purely descriptive and non-advisory.

Adverse Reaction Frequencies

Classification Examples of Documented Reactions
Very Common Upper respiratory infection
Common Headache, Abdominal pain, Nausea, Vomiting, Pyrexia (fever), Rash, Elevated liver enzymes
Uncommon Agitation, Anxiety, Insomnia, Dizziness, Somnolence, Nosebleeds
Rare/Very Rare Anaphylaxis, Churg-Strauss syndrome, Suicidal thoughts and behaviour, Hepatitis, Stevens-Johnson syndrome

System-Organ Classes and Serious Reactions

Adverse effects are documented across various systems, including the Gastrointestinal, Nervous, and Immune Systems. Of particular regulatory focus are Psychiatric Disorders, with reported events spanning agitation, depression, and, in rare instances, suicidal ideation and behaviour. This risk is highlighted in official labeling.

Serious systemic events, though rare, include eosinophilic conditions like Churg-Strauss syndrome and instances of Hepatitis. These systemic events are officially noted, sometimes with context relating to the reduction of concurrent corticosteroid therapy.

Safety-Related Restrictions

Official labeling contains specific constraints on the medicine's use. Montelukast is not indicated for the treatment of acute asthma attacks or status asthmaticus. Furthermore, the medicine must not be abruptly substituted for inhaled or oral corticosteroids, a key safety restriction documented in prescribing information. Population-specific notes indicate that use in severe hepatic impairment has not been studied and data is noted for pediatric patients across different age brackets.

Overdose and Emergency Response

The regulatory information for Asmakast (Montelukast) overdose is strictly defined by documented clinical outcomes and required supportive actions. The official prescribing information cites reports of acute overdosage in adults, adolescents, and children with reported single doses as high as 1000 mg.

Documented Overdose Signs and Required Action Official Regulatory Statement
Manifestations Acute overdosage has been associated with manifestations including abdominal pain, somnolence (drowsiness), thirst, headache, vomiting, and psychomotor hyperactivity.
Emergency Action Urgent medical attention is required for the management of the overdosage, which is strictly defined as symptomatic and supportive.
Overdose Management Constraints Official Regulatory Statement
Specific Antidote Regulatory labeling states there is no specific information available on the existence of a dedicated antidote.
Removal Procedures It is unknown if Montelukast can be effectively removed from the body using hemodialysis or peritoneal dialysis, limiting these procedural options.

The overall overdose profile is structured by these findings. The documented symptoms observed across all age groups serve as the clear indicator for seeking immediate professional medical care. The management plan is strictly directed toward symptomatic and supportive treatment, given the absence of a known specific reversal agent and the undetermined efficacy of extracorporeal clearance methods like dialysis.

Therapeutic Uses of Asmakast

What Asmakast Treats: Main Uses and Benefits

Asmakast is commonly used for managing conditions involving symptoms related to inflammatory or irritative states of the respiratory system, providing essential supportive relief. The primary uses are aligned with the established therapeutic areas for the management of respiratory symptoms.

This medication is generally used for the prophylaxis and long-term control of asthma, for the management of symptoms related to allergic rhinitis (both seasonal and perennial), and as a preventative measure for exercise-induced bronchoconstriction (EIB).

The application of this medication contributes to easing the overall symptom load across these conditions, supporting patients during episodes of heightened discomfort.

“This therapy provides supportive relief when symptoms interfere with routine activities.”


Quick Fact: Relief for Respiratory Discomfort
Symptom Clusters Addressed: Persistent wheezing and recurrent cough associated with asthma, and rhinitis symptoms like nasal congestion and runny nose.

Long-Term Control of Chronic Asthma

This medication is generally used for the prophylaxis and long-term control of asthma, addressing symptoms that interfere with daily functioning. Its application contributes to easing the overall symptom load and may assist with maintaining functional stability.

Symptom Relief for Allergic Rhinitis

Asmakast is relevant for easing symptoms related to allergic inflammation in the nasal passages, applicable in both seasonal and perennial contexts. This use contributes to improved comfort during periods of heightened symptoms, supporting general well-being.

Management of Exercise-Triggered Airway Reactivity

It is also applied in situations where patients experience symptoms associated with acute or episodic changes following physical exertion. This prophylactic use supports general well-being during symptomatic phases and may help patients cope more steadily with symptom fluctuations related to physical activity.

Regulatory References

  1. NIH MedlinePlus Drug Information

Eligibility and Restrictions for Use

This section outlines the officially documented population eligibility rules for Asmakast (Montelukast) based on regulatory information. It is not intended as medical advice.


Contraindicated Populations and Conditional Use

Asmakast must not be used by individuals with a known hypersensitivity to Montelukast or any component of the product. It is also contraindicated for use in treating an acute asthma attack (acute bronchospasm).

Conditional use applies to patients taking the medicine for allergic rhinitis; regulators advise reserving its use for those who have an inadequate response or intolerance to alternative therapies.

Age Group Eligibility Status (by Indication)
Adults/Adolescents (ge 15 yrs) Use established for all approved uses.
Children (ge 6 yrs) Use established for asthma, allergic rhinitis, and prevention of Exercise-Induced Bronchoconstriction (EIB).
Toddlers (ge 12 months) Use established for asthma prophylaxis.
Infants (< 12 months) Use Not Established for asthma prophylaxis.

Organ Function and Physiological States

  • Organ Impairment: No dosage adjustment is necessary for patients with renal insufficiency or mild to moderate hepatic impairment. However, use in patients with severe hepatic impairment has not been assessed.
  • Pregnancy & Lactation: Use during pregnancy and lactation is generally considered acceptable only if clearly needed/essential, as official data have not established an associated risk of congenital disabilities, and excretion into human milk is documented.

What should I know about interactions with other medicines?

Interactions with Other Medicines

Asmakast (Montelukast Sodium) can interact with certain other medicinal products, which may alter the concentration of Asmakast in the body or the activity of the other medicine. Patients should provide their healthcare provider with a complete list of all prescription, nonprescription, vitamin, and herbal supplements they are currently taking.

Key Interacting Medicinal Products and Categories

Product Category / Specific Medicine Effect on Asmakast or Other Medicine
Strong Cytochrome P450 Enzyme Inducers (e.g., Rifampin, Phenobarbital) Can decrease the concentration of Asmakast in the bloodstream.
Gemfibrozil (for high cholesterol) May significantly increase the concentration of Asmakast in the bloodstream.

Interaction Details

  • Rifampin is a medicine used to treat conditions like tuberculosis. Co-administration with Rifampin, a potent enzyme inducer, has been shown to decrease the plasma exposure of Asmakast by approximately 40%. Despite this change, no dosage adjustment for Asmakast is typically recommended based on clinical study findings.
  • Asmakast itself is generally not anticipated to cause clinically significant changes in the metabolism of most other common medicines. Studies have shown that Asmakast does not significantly alter the activity of medicines such as warfarin, theophylline, digoxin, or oral contraceptives containing ethinyl estradiol and norethindrone.

Important Note: Individuals with asthma whose symptoms are worsened by aspirin or Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) should continue to avoid these products while taking Asmakast.

Mechanism of Action

Selective Blockade of CysLT₁ Receptors

This domain covers the molecular target and the specific action of the drug's active ingredient. The action is centered on the Cysteinyl Leukotriene Receptor Type 1 (CysLT1 receptor), where the molecule acts as a selective antagonist. By binding to this receptor, the drug competitively blocks endogenous inflammatory messengers, chiefly Leukotriene D4 (LTD4), from docking and initiating a cell signal. This fundamental step defines the drug's activity as specific to this eicosanoid pathway.


️ Modulation of Airway Smooth Muscle Tone and Fluid Leakage

This section explains the cellular and tissue-level effects resulting from the receptor blockade. The drug's mechanism intervenes in the inflammatory-contractile cascade driven by Leukotrienes. Preventing LTD4 signaling stops the activation of secondary messengers that cause airway smooth muscle to contract and increases vascular permeability. This action curtails local fluid leakage (edema) and modulates underlying tissue tone.


Modulation of Airway Hyperresponsiveness

This domain links the molecular and cellular actions to the resulting physiological profile. By simultaneously inhibiting bronchoconstriction signals and dampening the inflammatory response (including the recruitment of inflammatory cells like eosinophils), the drug modulates key pathways associated with heightened physiological responses. The result is modulation of the physiological state known as airway hyperresponsiveness (AHR), correlating to the preservation of basal airway patency.

Dosage and Administration Information

Asmakast is strictly administered via the oral route, available in multiple formulations, including the 10 mg film-coated tablet, 4 mg and 5 mg chewable tablets, and 4 mg oral granules. For chronic management of relevant conditions, the standard regimen for adults and adolescents (ge 15 years) is 10 mg once daily. This frequency pattern establishes a requirement for long-term, continuous administration. The tablets may be taken with or without food. Dosage adjustments are not required for older adults or in patients with renal or mild-to-moderate hepatic impairment.

Administration Timing and Special Conditions

The use of this medication is highly dependent on the condition being addressed, structuring the time of intake:

  • For chronic asthma treatment (or when combined with allergic rhinitis), the dose should generally be taken in the evening.
  • For allergic rhinitis alone, the daily dose may be taken in the morning or evening.
  • For the prophylaxis of exercise-induced bronchoconstriction (EIB), a single 10 mg dose must be administered at least two hours prior to the activity, with a strict constraint of not taking a second dose within 24 hours.

Preparation of Oral Granules

The oral granule packets require specific preparation steps: the contents must be administered within 15 minutes of opening. The granules should be mixed with 5 mL of room temperature liquid (such as baby formula or breast milk) or a spoonful of soft food (such as applesauce or ice cream) before immediate swallowing. If a daily dose is missed, the standard procedure is to resume the next dose at the regular time, without taking two doses concurrently.

Recent Clinical Evidence

Research Evidence: Overview of Studies for Asmakast

How to Understand Clinical Trial Information

When reviewing research on Asmakast, it helps to understand how studies are conducted. Most research involves Randomized Controlled Trials (RCTs), where people are randomly assigned to receive either Asmakast or a placebo (an inactive substance) or another treatment. Researchers then monitor outcomes, such as changes in lung function (often measured by FEV1, which assesses how much air you can exhale) and patient-reported outcomes describing perceived discomfort. The evidence presented below reflects group patterns observed in these specific studies, and research does not determine whether an individual will respond similarly.


Evidence for Use in Managing Chronic Asthma

Studies conducted during periods of increased symptom activity used in research exploring how symptoms change over time to evaluate Asmakast in research contexts for chronic asthma. Research examined various outcomes related to systemic or functional imbalance, including measurements of lung function and patient-reported outcomes describing perceived discomfort and activity level. These studies included adults and children aged 6 and older with mild to moderate persistent asthma.

The findings describe patterns observed in the studies where groups receiving Asmakast studies reported observed mean changes in measured lung function compared to the placebo groups over the trial duration. Studies monitored how symptoms evolved in the observed populations, and trials described patterns of reported symptoms and rescue medication use were observed in the Asmakast groups compared to the placebo groups in the short term.


Evidence for Preventing Exercise-Induced Bronchoconstriction (EIB)

Asmakast was evaluated in specialized short-term studies, including cross-over study designs, focusing on Research examining Asmakast in the context of exercise-induced symptoms. Studies examined outcomes related to systemic or functional imbalance and fluctuating symptom patterns. Research examined the duration of protection and changes in FEV1 measurements following a standardized, laboratory-based exercise challenge.

Following single or short-term administration, studies monitored objective outcomes related to systemic or functional imbalance, and data show patterns related to FEV1 measurements compared to placebo. Research exploring short-term symptom changes described variability in the reported length of time the acute changes were sustained after administration.


Limitations and What Remains Uncertain About Asmakast Evidence

The majority of the evidence is derived from studies with follow-up durations that were limited, typically lasting a few weeks up to six months. Long-term effects are not fully established, and evidence is limited regarding the durability or consistency of the reported findings for periods exceeding one year. Similarly, studies focusing on patients with co-existing chronic conditions are limited, meaning results apply only to the populations studied and may not reflect the complexity of conditions characterized by fluctuating or episodic manifestations.

Key Studies & References

  1. GINA 2023 - Global Strategy for Asthma Management and Prevention (Full Report)

Frequently Asked Questions (FAQ)

Common questions about Asmakast (FAQ)

Q: How quickly does Asmakast start working for breathing issues?

A: Asmakast is rapidly absorbed after being taken by mouth, with the highest concentration of the active ingredient in the bloodstream typically reached in about three to four hours for the tablet form. Official information indicates that this medicine is intended for chronic management, and clinical studies have been conducted on its use when taken consistently.

Q: Why do some people take Asmakast at night?

A: For the ongoing management of chronic asthma, or when the treatment combines asthma and allergic rhinitis, the official administration instructions state that the dose should generally be taken once daily in the evening. The timing preference is based on the administration schedule used and evaluated in specific clinical trials.

Q: Is Asmakast a preventative medicine or a rescue treatment?

A: Asmakast is designated for the prophylaxis and chronic, long-term treatment of conditions like asthma. Official safety information specifies that this medicine is not indicated for use as a rescue medicine to reverse acute episodes of shortness of breath or bronchospasm.

Q: What is the difference between Asmakast and a bronchodilator?

A: Asmakast is classified as a Leukotriene Receptor Antagonist (LTRA); it works by blocking inflammatory messengers called leukotrienes. This differs from bronchodilators, which are a class of medicines that act by directly relaxing the airway muscles to provide rapid relief. The official labeling confirms that Asmakast is not a bronchodilator for treating acute attacks.

Q: Is Asmakast the same type of medicine as an inhaler?

A: No. Asmakast is formulated for oral use (as a tablet, chewable tablet, or granules), meaning it works systemically (throughout the body). This differs from most common rescue medicines, which are typically delivered via an inhaler to provide rapid, localized relief directly to the airways.

Q: Can Asmakast be taken long-term?

A: Official regulatory documents indicate that Asmakast is used for the chronic treatment of asthma. Official labeling notes that patients on long-term treatment are typically monitored regularly by their healthcare provider to check for effects.

Q: Can Asmakast be split or crushed?

A: Official preparation instructions for the oral granules provide specific steps for mixing them with soft food or liquid. However, the regulatory labeling for the film-coated and chewable tablets does not include any instructions for splitting or crushing these forms, which is generally understood to mean they are to be swallowed whole as formulated.

Q: What happens if I stop taking Asmakast suddenly?

A: Official safety instructions caution that Asmakast must not be abruptly substituted for inhaled or oral corticosteroids. Furthermore, official guidance states that if a user or caregiver observes concerning changes in behavior or new neuropsychiatric symptoms, they should stop the medicine and contact a healthcare provider immediately.

Q: Does Asmakast interact with alcohol?

A: The official product labeling does not report a specific interaction between Asmakast and alcohol. However, it is noted that Montelukast has been linked to elevated liver enzymes and rare instances of liver injury (hepatitis) in post-marketing reports. The effect of excessive alcohol consumption on the liver is a general consideration for any medicine that affects the liver.

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

A: Clinical studies indicate that Asmakast does not typically affect the metabolism of most other common medicines, including non-steroidal anti-inflammatory agents (NSAIDs). However, official documentation notes that individuals with asthma whose symptoms are known to be worsened by aspirin or NSAIDs should continue to avoid these products.

Q: Can Asmakast cause weight changes?

A: Weight changes are not listed among the very common, common, or less common adverse reactions that were documented in the official clinical trials or post-marketing surveillance sections of the product labeling.

Q: Does Asmakast require special monitoring?

A: Official labeling states that patients and caregivers should be alert for changes in behavior or new neuropsychiatric symptoms when the medicine is used. For individuals on long-term treatment, regular check-ups with a healthcare provider are a standard part of care.

Q: What does the research say about Asmakast's use in exercise-induced symptoms?

A: Research has shown that a single dose of Asmakast provided a protective effect against exercise-induced bronchoconstriction (EIB) for up to 24 hours following administration. The medication is officially indicated for the prevention of EIB in specific age groups, according to regulatory sources.

Q: Is Asmakast considered a first-line treatment?

A: Official labeling indicates that for the treatment of allergic rhinitis (seasonal or perennial), the use of Asmakast should be reserved for patients who have not responded adequately to or cannot tolerate alternative therapies.

Q: Are there known genetic factors that affect how Asmakast works?

A: Official information indicates that the drug is primarily processed by the liver using specific enzymes, such as CYP2C8. Genetic variations in these metabolizing enzymes can influence the concentration of the medicine in the body, as noted in authoritative sources.

Q: Is Asmakast available in different strengths or forms?

A: Yes. According to official product labeling, Asmakast is available in a 10 mg film-coated tablet, 4 mg and 5 mg chewable tablets, and a 4 mg oral granules formulation.

How should Asmakast be stored and disposed of?

How to Store and Dispose of Asmakast

The storage and disposal of Asmakast (montelukast sodium) must strictly follow the conditions defined in the official regulatory labeling to maintain product stability and safety.

Storage Requirements

Asmakast must be stored at Controlled Room Temperature, which is between 20 C to 25 C (68 F to 77 F), with excursions permitted up to 30 C (86 F). The medication must be kept in its original container and protected from both light and moisture. The oral granule formulation requires the contents of the packet to be administered within 15 minutes of opening; the opened contents or mixed material must not be stored.

Disposal and Safety

All medicine must be stored out of the reach of children. Unused or expired Asmakast should be disposed of in accordance with local requirements for pharmaceutical waste, such as utilizing drug take-back programs or following FDA guidance for safe household trash disposal.

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

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