N-Kast-L Tablets

Description

N-Kast-L Tablets (Montelukast 10mg & Levocetirizine 5mg) – Complete Reference

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1. Pharmacokinetics

Montelukast (10mg):

Absorption: Montelukast is well absorbed after oral administration, with peak plasma concentrations occurring within 3–4 hours.

Distribution: It is widely distributed in plasma and is highly protein-bound (99%).

Metabolism: Metabolized in the liver primarily via cytochrome P450 enzymes, mainly CYP3A4.

Excretion: Excreted predominantly via the feces (~86%) and a small amount in the urine (~6%).

Half-life: The elimination half-life is approximately 2.7 to 5.5 hours in adults.

Levocetirizine (5mg):

Absorption: Levocetirizine is rapidly absorbed with peak plasma concentration within 0.9 hours.

Distribution: It is moderately protein-bound (90%) and distributes throughout the body.

Metabolism: Levocetirizine undergoes minimal metabolism, primarily excreted unchanged in the urine.

Excretion: The drug is excreted unchanged in the urine.

Half-life: The half-life is approximately 8 hours in healthy adults.

 

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2. Pharmacodynamics

Montelukast (10mg):

Class: Leukotriene receptor antagonist.

Action: Montelukast selectively binds to and inhibits the cysteinyl leukotriene receptor (CysLT1), blocking the action of leukotrienes, which are involved in the inflammatory process in asthma and allergic rhinitis.

Effect: Reduces bronchoconstriction, inflammation, and mucus production in the airways, thus improving breathing and reducing allergy symptoms.

Levocetirizine (5mg):

Class: Second-generation antihistamine.

Action: Levocetirizine is a selective H1-antagonist, inhibiting the action of histamine at H1 receptors.

Effect: Provides relief from allergic symptoms such as sneezing, runny nose, and itching by preventing histamine-mediated inflammation and vasodilation.

 

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3. Clinical Indications

Allergic Rhinitis: Relief from symptoms such as sneezing, nasal congestion, and itching.

Asthma: Management of chronic asthma, including prevention of exercise-induced bronchoconstriction.

Seasonal and Perennial Allergies: Reduces the severity of symptoms associated with seasonal or perennial allergic rhinitis.

Chronic Urticaria: For relief from symptoms of chronic hives or itching.

 

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4. Dosage Recommendations

Adults and Children (12 years and above):

Asthma & Allergic Rhinitis: 1 tablet (10mg Montelukast & 5mg Levocetirizine) once daily, preferably in the evening.

Children (6 to 12 years):

Asthma & Allergic Rhinitis: 1 tablet (5mg Montelukast & 2.5mg Levocetirizine) once daily, preferably in the evening.

Administration: Take the tablet whole with or without food. It is recommended to be taken at the same time every day for optimal effect.

 

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5. Safety Precautions

Allergy: Contraindicated in patients with hypersensitivity to Montelukast, Levocetirizine, or any components of the formulation.

Liver Impairment: Use with caution in patients with hepatic impairment; dose adjustments may be necessary for Montelukast.

Renal Impairment: Use with caution in patients with severe renal impairment, especially for Levocetirizine.

Pregnancy and Lactation: Montelukast is classified as Category B during pregnancy. Levocetirizine should be used with caution during pregnancy and lactation.

Elderly: Elderly patients may require dose adjustments, particularly for Levocetirizine due to possible reduced renal function.

CNS Effects: Levocetirizine may cause drowsiness; avoid operating heavy machinery or driving if you experience sedation.

Neuropsychiatric Effects: Monitor for changes in behavior or mood, especially in children, as Montelukast may be associated with neuropsychiatric effects.

 

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6. Side Effects

Montelukast (10mg):

Common: Headache, abdominal pain, fatigue, dizziness, and sore throat.

Serious (rare): Neuropsychiatric symptoms such as aggression, agitation, hallucinations, depression, or suicidal thoughts.

Levocetirizine (5mg):

Common: Drowsiness, dry mouth, headache, and dizziness.

Serious (rare): Tachycardia, difficulty urinating, allergic reactions (e.g., rash, swelling).

 

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7. Storage and Stability

Storage: Store at room temperature, below 30°C, in a dry place, and away from direct sunlight.

Shelf-life: 2–3 years.

Note: Keep out of reach of children.

 

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8. Overdose Management

Symptoms of Overdose: Overdose may cause symptoms like drowsiness, restlessness, or agitation.

Treatment: Symptomatic treatment. There is no specific antidote. In cases of significant overdose, supportive care is recommended.

 

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9. Additional Notes

Drug Interactions: Caution when co-administering with CYP3A4 inducers or inhibitors, as they may affect Montelukast metabolism. Levocetirizine should be used with caution in combination with other CNS depressants.

Monitoring: Monitor for any neuropsychiatric symptoms, particularly in children, and for changes in renal function with prolonged use