MONTAB-LC

Description

PHARMACOLOGICAL PROPERTIES:

Pharmacodynamic properties:

Levocetirizine Dihydrochloride:

Mechanism of action

Levocetirizine selectively inhibits histamine H₁ receptors. This action prevents histamine from activating this receptor and causing effects like smooth muscle contraction, increased permeability of vascular endothelium, histidine uptake in basophils, stimulation of cough receptors, and stimulation of flare responses in the nervous system.

Pharmacodynamic effects

Levocetirizine is a second generation histamine H₁ antagonist used to treat various allergic symptoms. It has a long duration of action as it is generally taken once daily.

Montelukast Sodium:

Mechanism of action

Cysteinyl leukotrienes (CysLT) like LTC4, LTD4, and LTE4, among others, are eicosanoids released by a variety of cells like mast cells and eosinophils. When such CysLT bind to corresponding CysLT receptors like CysLT type-1 receptors located on respiratory airway smooth muscle cells, airway macrophages, and on various pro-inflammatory cells like eosinophils and some specific myeloid stem cells activities that facilitate the pathophysiology of asthma and allergic rhinitis are stimulated.

Pharmacodynamic effects

Montelukast causes inhibition of airway cysteinyl leukotriene receptors as demonstrated by the ability to inhibit bronchoconstriction due to inhaled LTD 4 in asthmatics. Doses as low as 5 mg cause substantial blockage of LTD 4 -induced bronchoconstriction.

Pharmacokinetic properties: Levocetirizine Dihydrochloride:

Absorption

Levocetirizine is rapidly and extensively absorbed following oral administration. Peak plasma concentrations are achieved 0.9 g h after dosing. Steady state is achieved after two days.

Distribution

The volume of distribution of levocetirizine is 0.33±0.02L/kg.

Metabolism

Levocetirizine is poorly metabolized with 85.8% of an oral dose being excreted as the unchanged drug. Levocetirizine can be metabolized to a dihydrodiol, an N-oxide, a hydroxymethoxy derivative, a hydroxy derivative, an O-dealkylated derivative, a taurine conjugate, and an N-dealkylated and aromatic hydroxylated derivative.

Elimination

168 hours post dose an average of 85.4% of a radiolabeled dose was recovered with an average of 80.8% in the urine and 9.5% in the feces

Montelukast Sodium:

Absorption

After administration of the 10 mg film-coated tablet to fasted adults, the mean peak montelukast plasma concentration (Cmax) is achieved in 3 to 4 hours (Tmax). The mean oral bioavailability is 64%.

Distribution

Montelukast is more than 99% bound to plasma proteins. The steady-state volume of distribution of montelukast averages 8 to 11 liters.

Metabolism

montelukast is highly metabolized and typically so by the cytochrome P450 3A4, 2C8, and 2C9 isoenzymes.

Elimination

Montelukast and its metabolites are almost exclusively excreted in the bile and into the feces.

THERAPEUTIC CLASS: Anti Allergic

 CLINICAL PARTICULARS:

Therapeutic Indication:

• Levocetirizine Dihydrochloride & Montelukast Sodium Tablet is indicated for relief and/or prevention of symptoms of allergic rhinitis (seasonal and perennial).

Posology and method of Administration:

Posology:

Adults (>15 years): 1 tablet once daily

Method of Administration: Oral

Missed Dose:

If one dose is missed, this dose should be omitted and the next dose should be taken at the usual time with a meal. Do not take a double dose to make up for a forgotten dose.

CONTRAINDICATIONS:

• Patients who are hypersensitive to any component of this product or to montelukast, sodium levocetirizine, or cetirizine. Patients with completely impaired renal function (anuria).

SIDE EFFECTS:

Dyspepsia, abdominal pain, rash, dizziness, headache, fatigue, and somnolence. Sometimes, hypersensitivity, irritability, restlessness, insomnia, vomiting and diarrhoea

SPECIAL WARNINGS AND PRECAUTIONS FOR USE:

• Precaution is recommended with intake of alcohol and in those who are on CNS depressants. Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose galactose malabsorption should not take this medicine.
• As Levocetirizine is mainly excreted through urine, dosage adjustment may be required in patients with impaired renal function. Hence this combination should be used with caution in such patients.
• As montelukast is mainly excreted through bile, caution is to be exercise while prescribing this combination in patients with impaired hepatic function.

OTHER MEDICINES AND MONTELUKAST AND LEVOCETIRIZINE TABLETS:

• The serum concentration of Montelukast can be increased when it is combined with Abametapir.
• The metabolism of Montelukast can be increased when combined with Abatacept.
• The risk or severity of CNS depression can be increased when Levocetirizine is combined with 1,2-Benzodiazepine.
• Aceclofenac may decrease the excretion rate of Levocetirizine which could result in a higher serum level.

PREGNANCY AND BREAST-FEEDING

• As montelukast is mainly excreted through bile, caution is to be exercise while prescribing this combination in patients with impaired hepatic function.
• Since levocetirizine is excreted in breast-milk the combination is not recommended during lactation.

DRIVING AND USING MACHINES

Montelukast is not expected to affect a patient’s ability to drive a car or operate machinery.

measurements of driving ability, sleep latency and assembly line performance have not demonstrated any clinically relevant effects at the recommended dose of 5 mg of levocetirizine.

OVER DOSE:

Somnolence, gastrointestinal disturbances (e.g. nausea and vomiting), tachycardia, tremor, agitation and dizziness.

 STORAGE:

Store in a cool dry place away from direct sunlight. Keep out of reach of children